Topography, Landforms, and Geomorphology Designed to meet South Carolina Department of Education...

Topography, Topography, Landforms, and Landforms, and GeomorphologyGeomorphology

Designed to meet South Carolina Designed to meet South Carolina

Department of Education Department of Education

2005 Science Academic Standards2005 Science Academic Standards

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Table of Contents 1 of 4Table of Contents 1 of 4 Topography, Landforms, and Geomorphology: Basic Definitions (Topography, Landforms, and Geomorphology: Basic Definitions (slide 6) (Standards: ) (Standards: 3-3, , 5-3, , 8-3) )

Topography (Topography (slide 7) (Standards: ) (Standards: 3-3, , 5-3, , 8-3) ) Landforms (Landforms (slide 8) (Standards: ) (Standards: 3-3, , 5-3, , 8-3) ) Landforms and Scale: Crustal Orders of Relief (Landforms and Scale: Crustal Orders of Relief (slides 9 - - 10) (Standards: ) (Standards: 3-3, , 5-3, , 8-3) ) Geomorphology (Geomorphology (slide 11) (Standards: ) (Standards: 3-3, , 5-3, , 8-3) ) Uniformitarianism (Uniformitarianism (slide 12) (Standards: ) (Standards: 3-3.8, , 8-3.7) ) Constructive and Destructive Processes (Constructive and Destructive Processes (slides 13 , , 14, and , and 15) (Standards: ) (Standards: 5-3.1))

Genetic Landform Classification (Genetic Landform Classification (slide 16) (Standards: ) (Standards: 3-3, , 5-3, , 8-3) ) Landforms: (Landforms: (slides 17 - - 118) (Standards: ) (Standards: 3-3, , 5-3, , 8-3) )

Tectonic Landforms (Tectonic Landforms (slide 17) (Standards: ) (Standards: 3-3, , 5-3, , 8-3) ) Orogenesis (Orogenesis (slide 18) (Standards: ) (Standards: 3-3.6, , 5-3.1, , 8-3.7)) Deformation (Deformation (slide 19) (Standards: ) (Standards: 8-3.7))

Folding (Folding (slides 20, , 21, and , and 22) (Standards: ) (Standards: 3-3.6, , 5-3.1, , 8-3.7, , 8-3.9)) Faulting (Faulting (slides 23 , , 24, and , and 25) (Standards: ) (Standards: 3-3.6, , 5-3.1, , 8-3.7, , 8-3.9)) Fractures and Joints (Fractures and Joints (slide 26) (Standards: ) (Standards: 3-3.6, , 5-3.1, , 8-3.7, , 8-3.9)) Jointing (Jointing (slide 27) (Standards: ) (Standards: 3-3.6, , 5-3.1, , 8-3.7, , 8-3.9))

Domes and Basins (Domes and Basins (slide 28) (Standards: ) (Standards: 8-3.7, , 8-3.9)) Horst and Graben: Basin and Range (Horst and Graben: Basin and Range (slide 29) (Standards: ) (Standards: 5-3.1, , 8-3.7, , 8-3.9)) Rift Valleys (Rift Valleys (slide 30) (Standards: ) (Standards: 5-3.1, , 5-3.2, , 8-3.7, , 8-3.9)) Major Mountain Ranges of the World (Major Mountain Ranges of the World (slide 31) (Standards: ) (Standards: 3-3.6,, 8-3.9))

Rocky Mountains (Rocky Mountains (slide 32) (Standards: ) (Standards: 3-3.6, , 5-3.1, , 8-3.7,, 8-3.9)) Appalachian Mountains (Appalachian Mountains (slide 33) (Standards: ) (Standards: 3-3.6, , 5-3.1, , 8-3.7,, 8-3.9)) Andes Mountains (Andes Mountains (slide 34) (Standards: ) (Standards: 3-3.6, , 5-3.1, , 8-3.7,, 8-3.9)) European Alps (European Alps (slide 35) (Standards: ) (Standards: 3-3.6, , 5-3.1, , 8-3.7,, 8-3.9)) Himalayan (Himalayan (slide 36)) (Standards: (Standards: 3-3.6, , 5-3.1, , 8-3.7,, 8-3.9))

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Table of Contents 2 of 4Table of Contents 2 of 4 Volcanic Landforms: Extrusive Igneous (Volcanic Landforms: Extrusive Igneous (slides 37 - - 45) (Standards: ) (Standards: 3-3, , 5-3, , 8-3) )

Cinder Cones (Cinder Cones (slide 38) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9)) Shield Volcanoes (Shield Volcanoes (slide 39) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9)) Strato-Volcanoes (Strato-Volcanoes (slide 40) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9)) Caldera (Caldera (slide 41) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9)) Lava Domes (Lava Domes (slide 42) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9)) Volcanic Hot Spots (Volcanic Hot Spots (slide 43) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9)) Volcanic Necks (Volcanic Necks (slide 44) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9)) Flood Basalts (Flood Basalts (slide 45) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9))

Volcanic Landforms: Intrusive Igneous (Volcanic Landforms: Intrusive Igneous (slides 46 - - 50) (Standards: ) (Standards: 3-3, , 5-3, , 8-3) ) Batholiths (Batholiths (slide 47) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9)) Plutons (Plutons (slide 48) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9)) Sills, Laccoliths, Dikes (slide 49) (Standards: Sills, Laccoliths, Dikes (slide 49) (Standards: 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9)) Monadnocks (Monadnocks (slide 50) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9) )

River Systems and Fluvial Landforms (River Systems and Fluvial Landforms (slides 51 - - 69) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9))

Rivers Systems and Fluvial Processes (Rivers Systems and Fluvial Processes (slide 52) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9))

Longitudinal Profile and Watersheds (Longitudinal Profile and Watersheds (slides 53 and and 54) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9))

South Carolina River and Basins (South Carolina River and Basins (slide 55) (Standards:) (Standards: 3-3.5, , 3-3.6, , 8-3.9)) Dams and Lakes (Dams and Lakes (slide 56) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Mountain Streams (Mountain Streams (slide 57) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Braided (Braided (slide 58) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Meandering (Meandering (slide 59) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Entrenched Meanders (Entrenched Meanders (slide 60) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Anabranching (Anabranching (slide 61) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9))

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Table of Contents 3 of 4Table of Contents 3 of 4 River cont. (River cont. (slides 51 - - 69) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9))

Straight (Straight (slide 62) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Flood Plains (Flood Plains (slide 63, , 64, and , and 65) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) River Terraces (River Terraces (slide 66) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Waterfalls (Waterfalls (slide 67) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Alluvial Fans (Alluvial Fans (slide 68) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Gullys (Gullys (slide 69) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9))

Karst Landforms (Karst Landforms (slides 70 - - 75) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Caverns (Caverns (slide 71) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Sinkholes (Sinkholes (slide 72) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Disappearing Streams (Disappearing Streams (slide 73) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Springs (Springs (slide 74) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Towers (Towers (slide 75) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9))

Aeolian Landforms (Aeolian Landforms (slides 76 - - 82) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Dunes (Dunes (slides 77 and and 78) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Loess (Loess (slide 79) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Yardang (Yardang (slide 80) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Riverine Dunes and Sand Sheets (Riverine Dunes and Sand Sheets (slide 81) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Carolina Bays (Carolina Bays (slide 82) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9))

Coastal Landforms (Coastal Landforms (slides 83 - - 87) (Standards: ) (Standards: 3-3.6, , 3-3.8, , 5-3.1,, 8-3.7, , 8-3.9)) Littoral Zone (Littoral Zone (slide 84) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 5-3.4, , 8-3.7, , 8-3.9)) Beaches (Beaches (slide 85) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 5-3.4, , 8-3.7, , 8-3.9)) Barrier Islands (Barrier Islands (slide 86) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 5-3.4, , 8-3.7, , 8-3.9)) Beach Ridges (Beach Ridges (slide 87) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 5-3.4, , 8-3.7, , 8-3.9)) Spits (Spits (slide 88) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 5-3.4, , 8-3.7, , 8-3.9)) Deltas (Deltas (slides 89 and and 90) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 5-3.4, , 8-3.7, , 8-3.9))

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Table of Contents 4 of 4Table of Contents 4 of 4 Coastal Landforms Cont. (Coastal Landforms Cont. (slides 88 - - 94) (Standards: ) (Standards: 3-3, , 5-3, , 8-3) )

Sea Cliffs (Sea Cliffs (slide 91) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 5-3.4, , 8-3.7, , 8-3.9)) Sea Arch (Sea Arch (slide 92) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 5-3.4, , 8-3.7, , 8-3.9)) Wave-Cut Scarps (Wave-Cut Scarps (slide 93) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 5-3.4, , 8-3.7, , 8-3.9)) Marine Terraces (Marine Terraces (slide 94) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 3-3.8, , 5-3.1,, 5-3.4, , 8-3.7, , 8-3.9)) Continental Shelf and Slope (Continental Shelf and Slope (slide 95) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 5-3.1,, 5-3.2, , 8-3.7, , 8-3.9)) Ocean Basin (Ocean Basin (slide 96) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 5-3.1,, 5-3.2, , 8-3.7, , 8-3.9)) Abyssal Plains, Seamounts, Trenches (Abyssal Plains, Seamounts, Trenches (slide 97) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 5-3.1,, 5-3.2, , 8-3.7, , 8-3.9)) Mid-ocean Ridge (Mid-ocean Ridge (slide 98) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 5-3.1,, 5-3.2, , 8-3.7, , 8-3.9)) Rift Zone (Rift Zone (slide 99) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 5-3.1,, 5-3.2, , 8-3.7, , 8-3.9)) Ocean Floor Topography and Features (Ocean Floor Topography and Features (slide 100) (Standards: ) (Standards: 3-3.5, , 3-3.6, , 5-3.1,, 5-3.2, , 8-3.7, ,

8-3.9)) Glacial Landforms (Glacial Landforms (slides 101 - - 118) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 3-3.8, , 5-3.1, , 5-3.5, , 8-3.7, , 8-3.9))

Ice Sheets and Alpine Glaciers (Ice Sheets and Alpine Glaciers (slide 103) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 3-3.8, , 5-3.1, , 5-3.5, , 8-3.7, , 8-3.9)) Ice Field and Ice Caps (Ice Field and Ice Caps (slide 104) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 5-3.1, , 5-3.5, , 8-3.7, , 8-3.9)) Piedmont Glacier (Piedmont Glacier (slide 105) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 5-3.1, , 5-3.5, , 8-3.7, , 8-3.9)) Tidal Glaciers and Icebergs (Tidal Glaciers and Icebergs (slide 106) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 5-3.1, , 5-3.5, , 8-3.7, , 8-3.9)) Glacial U-shaped Valleys (Glacial U-shaped Valleys (slide 107) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 3-3.8, , 5-3.1, , 5-3.5, , 8-3.7, , 8-3.9)) Fjords (Fjords (slide 108) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 5-3.1, , 5-3.5, , 8-3.7, , 8-3.9)) Hanging Valleys (Hanging Valleys (slide 109) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 5-3.1, , 5-3.5, , 8-3.7, , 8-3.9)) Cirques and Cirque Glaciers (Cirques and Cirque Glaciers (slide 110) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 5-3.1, , 5-3.5, , 8-3.7, , 8-3.9)) ArArêêtes, Horns, and Cols (tes, Horns, and Cols (slide 111) (Standards: (Standards: 3-3.5,, 3-3.6, , 5-3.1, , 5-3.5, , 8-3.7, , 8-3.9)) Lateral and Medial Moraines (Lateral and Medial Moraines (slide 112) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 5-3.1, , 5-3.5, , 8-3.7, , 8-3.9)) Terminal and Recessional Moraines (Terminal and Recessional Moraines (slide 113) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 5-3.1, , 8-3.7, , 8-3.9)) Paternoster Lakes (Paternoster Lakes (slide 114) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 5-3.1, , 5-3.5, , 8-3.7, , 8-3.9)) Kettles (Kettles (slide 115) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 5-3.1, , 5-3.5, , 8-3.7, , 8-3.9)) Erratics (Erratics (slide 116) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 5-3.1, , 8-3.7, , 8-3.9)) Drumlins (Drumlins (slide 117) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 5-3.1, , 8-3.7, , 8-3.9)) Outwash Plains and Eskers (Outwash Plains and Eskers (slide 118) (Standards: ) (Standards: 3-3.5,, 3-3.6, , 3-3.8, , 5-3.1, , 8-3.7, , 8-3.9))

South Carolina Earth Science Education Standards Grades 3, 5, 8 (South Carolina Earth Science Education Standards Grades 3, 5, 8 (slides 119, , 120, and , and 121)) Resources and References (Resources and References (slide 122))

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Basic DefinitionsBasic Definitions

Topography Topography refers to the elevation and relief of the Earth’s refers to the elevation and relief of the Earth’s surface. surface.

Landforms Landforms areare the topographic featuresthe topographic features on the Earth’s on the Earth’s surface. surface.

GeomorphologyGeomorphology is the study of earth surface processes and is the study of earth surface processes and landforms. landforms.

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Standard: 3-3Standard: 5-3Standard: 8-3

The maps above represent the same area on Earth’s surface and they show three different ways we can view landforms. The image on the far left is a clip from a topographic elevation map, the image in the middle is an infrared aerial photo,

and the image on the right is the geologic interpretation of surface sediments and geomorphology. This location is interesting because it contains elements of a

natural and human altered physical environment. The lake in the image, (coded blue in the topographic and geology map, and black in the infrared aerial photo)

was formed by artificial damming a stream the flows through this landscape.

TopographyTopography Topography is a term used to describe the Earth’s surface. Topography Topography is a term used to describe the Earth’s surface. Topography

includes a variety of different features, collectively referred to as includes a variety of different features, collectively referred to as landforms.

Topography is measured by the differences in Topography is measured by the differences in elevation across the earth’s across the earth’s surface.surface.

Differences between high and low elevation are referred to as changes in Differences between high and low elevation are referred to as changes in relief..

Scientist examine topography using a variety of different sources ranging Scientist examine topography using a variety of different sources ranging from paper topographic maps to digital elevation models developed using from paper topographic maps to digital elevation models developed using specialized geographic information systems commonly referred to as a GIS. specialized geographic information systems commonly referred to as a GIS.

South Carolina’s elevation relief ranges from 4,590 feet in the BlueRidge Region to 0 feet along the

Coastal Plain. The rivers dissect the topography and drain

down-slope from headwaters in the mountainous Blue Ridge and

Piedmont, into the alluvial valleys of the Coastal Plain before

draining into the Atlantic Ocean.

Blue

Ridge

Blue

Ridge

Piedm

ont

Piedm

ont

Coast

al

Coast

al

Plain

Plain

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LandformsLandforms Landforms are the individual topographic features exposed on the Earth’s Landforms are the individual topographic features exposed on the Earth’s

surface.surface.

Landforms vary in size and shape and include features such as small creeks Landforms vary in size and shape and include features such as small creeks or sand dunes, or large features such as the Mississippi River or Blue Ridge or sand dunes, or large features such as the Mississippi River or Blue Ridge Mountains.Mountains.

Landforms develop over a range of different time-scales. Some landforms Landforms develop over a range of different time-scales. Some landforms develop rather quickly (over a few seconds, minutes, or hours), such as a develop rather quickly (over a few seconds, minutes, or hours), such as a landslide, while others may involve many millions of years to form, such as a landslide, while others may involve many millions of years to form, such as a mountain range.mountain range.

Landform development can be relatively simple and involve only a few Landform development can be relatively simple and involve only a few processes, or very complex and involve a combination of multiple processes processes, or very complex and involve a combination of multiple processes and agents.and agents.

Landforms are dynamic features that are continually affected by a variety of Landforms are dynamic features that are continually affected by a variety of earth-surface processes including weathering, erosion, and deposition. earth-surface processes including weathering, erosion, and deposition.

Earth scientists who study landforms provide decision makers with Earth scientists who study landforms provide decision makers with information to make natural resource, cultural management, and information to make natural resource, cultural management, and infrastructure decisions, that affect humans and the environment. infrastructure decisions, that affect humans and the environment.

Table Rock Mountain is a metamorphosed igneous intrusion exposed by millions of years of weathering and erosion in South Carolina’s Piedmont Region.

Photo Source: SCGSPhoto Source: SCGS

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Landforms and Scale:Landforms and Scale:Crustal Orders of ReliefCrustal Orders of Relief

First Order of Relief: The broadest landform scale is divided into The broadest landform scale is divided into continental landmasses, which , which

include all of the crust above sea-level (30% Earth’s surface), and include all of the crust above sea-level (30% Earth’s surface), and ocean basins, , which include the crustal areas below sea-level (70% of Earth’s surface)which include the crustal areas below sea-level (70% of Earth’s surface)

Second Order of Relief: The second order of relief includes regional-scale continental features such as The second order of relief includes regional-scale continental features such as

mountain ranges, plateaus, plains, and lowlands. Examples include the Rocky mountain ranges, plateaus, plains, and lowlands. Examples include the Rocky Mountains, Atlantic Coastal Plain, and Tibetan Plateau.Mountains, Atlantic Coastal Plain, and Tibetan Plateau.

Major ocean basin features including continental shelves, slopes, abyssal Major ocean basin features including continental shelves, slopes, abyssal plains, mid-ocean ridges, and plains, mid-ocean ridges, and trenches are all second-order relief landforms.

Third Order of Relief: The third order of relief includes individual landform features that collectively The third order of relief includes individual landform features that collectively

make up the larger second-order relief landforms. Examples include individual make up the larger second-order relief landforms. Examples include individual volcanoes, glaciers, valleys, rivers, flood plains, lakes, marine terraces, volcanoes, glaciers, valleys, rivers, flood plains, lakes, marine terraces, beaches, and dunes.beaches, and dunes.

Each major landform categorized within the third order of relief may also Each major landform categorized within the third order of relief may also contain many smaller features or different types of a single feature. For contain many smaller features or different types of a single feature. For example, although a flood plain is an individual landform it may also contain a example, although a flood plain is an individual landform it may also contain a mosaic of smaller landforms including pointbars, oxbow lakes, and natural mosaic of smaller landforms including pointbars, oxbow lakes, and natural levees. Rivers, although a single landform, may be classified by a variety of levees. Rivers, although a single landform, may be classified by a variety of channel types including straight, meandering, or braided. channel types including straight, meandering, or braided.

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Crustal Orders of ReliefCrustal Orders of Relief

1010

I. First Order or Relief: Continental Landmasses and Ocean Basins

II. Second Order of Relief:Major Continental and Ocean Landforms

III. Third Order of Relief:Genetic Landform Features

Table of ContentsImages and Photos: SCGS

Beaches Rivers and Flood Plains Mountains


GeomorphologyGeomorphology Geomorphology is the process-based study of landforms.Geomorphology is the process-based study of landforms.

Geo-morph-ology originates from Greek: originates from Greek: GeoGeo meaning the meaning the “Earth”, “Earth”, morph morph meaning its “shape”, and meaning its “shape”, and ology ology refers to “the refers to “the study of”.study of”.

Scientists who study landforms are Scientists who study landforms are Geomorphologists..

Geomorphology defines the processes and conditions that Geomorphology defines the processes and conditions that influence landform development, and the physical, morphological, influence landform development, and the physical, morphological, and structural characteristics of landforms. and structural characteristics of landforms.

Geomorphologists who study landforms often seek to answer Geomorphologists who study landforms often seek to answer fundamental questions that help them study landforms, such as:fundamental questions that help them study landforms, such as:

What is the physical form or shape of the landform? What is the physical form or shape of the landform? What is the elevation and topographic relief of the landform?What is the elevation and topographic relief of the landform? How did the landform originate?How did the landform originate? What is the distribution of the landform and where else does it What is the distribution of the landform and where else does it

occur?occur? Are their any patterns associated with the landform or Are their any patterns associated with the landform or

topography?topography? What is the significance of the landform in relation to other What is the significance of the landform in relation to other

elements of the landscape or environment?elements of the landscape or environment? Has the landform or geomorphology been altered by humans? Has the landform or geomorphology been altered by humans? Does the landform or geomorphology affect humans?Does the landform or geomorphology affect humans?

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UniformitarianismUniformitarianism Uniformitarianism is a common theory held by earth scientists that states Uniformitarianism is a common theory held by earth scientists that states

“the present is the key to the past”. Uniformitarianism implies that the Uniformitarianism implies that the processes currently shaping the Earth’s topography and landforms are the processes currently shaping the Earth’s topography and landforms are the same processes as those which occurred in the past.same processes as those which occurred in the past.

By studying geomorphology, we are better able to interpret the origin of By studying geomorphology, we are better able to interpret the origin of landforms and infer their future evolution within the landscape.landforms and infer their future evolution within the landscape.

Such applications are especially important for predicting, preventing, and Such applications are especially important for predicting, preventing, and mitigating natural hazards impact to humans, and managing our natural mitigating natural hazards impact to humans, and managing our natural resources for future generations. resources for future generations.

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The two images below illustrate the concept of uniformitarianism. On the left is an imprint of ripple marks in sandstone, similar current ripple forms in the

right image. If the present is the key to the past, we can infer that the sandstone rock formed in a low energy, fluvial environment similar to the

conditions in the right image.

Standard: 3-3.8Standard: 8-3.7

Constructive and Destructive Constructive and Destructive ProcessesProcesses

Constructive processes build landforms through tectonic and depositional processes.

Tectonic processes include movements at plate boundaries, movements at plate boundaries, earthquakes, orogeny, deformation, and volcanic activity.earthquakes, orogeny, deformation, and volcanic activity.

Deposition is the accumulation or accretion of weathered and is the accumulation or accretion of weathered and eroded materials.eroded materials.

Destructive processes break down landforms through weathering, erosion, and mass wasting.

Weathering is the disintegration of rocks by mechanical, chemical, is the disintegration of rocks by mechanical, chemical, and biological agents.and biological agents.

Erosion is the removal and transportation of weathered material by is the removal and transportation of weathered material by water, wind, ice, or gravity.water, wind, ice, or gravity.

Mass wasting is the rapid down-slope movement of materials by is the rapid down-slope movement of materials by gravity.gravity.

Other Agents and Processes that Affect Landform Development

Climate: temperature, precipitation, water cycle, atmospheric temperature, precipitation, water cycle, atmospheric conditionsconditions

Time: fast and slow rates of change : fast and slow rates of change People: influences on natural resources and earth surface

processes


Standard: 5-3.1

Constructive ProcessesConstructive Processes Constructive processesConstructive processes are responsible for physically building are responsible for physically building or constructing certain landforms. Constructive processes or constructing certain landforms. Constructive processes include include tectonic tectonic andand depositional processes depositional processes and their and their landforms.landforms.

Tectonic LandformsTectonic Landforms are created by massive earth movements due to are created by massive earth movements due to tectonic and volcanic activity, and include landforms such astectonic and volcanic activity, and include landforms such as: : mountains, mountains, rift valleys, volcanoes, and intrusive igneous landformsrift valleys, volcanoes, and intrusive igneous landforms

Depositional LandformsDepositional Landforms are produced from the deposition of weathered are produced from the deposition of weathered and eroded surface materials. Depositional landforms include features such and eroded surface materials. Depositional landforms include features such as: as: beaches, barrier islands, spits, deltas, flood plains, dunes, beaches, barrier islands, spits, deltas, flood plains, dunes, alluvial fans, and glacial moraines.alluvial fans, and glacial moraines.

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Standard: 5-3.1

Floodplain deposits at the confluence of Mississippi and

Arkansas Rivers.

The Stromboli Volcano erupting off the coast of Sicily in the

Mediterranean Sea.

Source: wikimedia commons Copyright ©Google Earth 200

Destructive ProcessesDestructive Processes DestructiveDestructive processes processes create landforms through create landforms through weathering weathering and and erosionerosion of surface materials facilitated by water, wind, of surface materials facilitated by water, wind, ice, and gravity. ice, and gravity. Mass-wasting eventsMass-wasting events occur in areas where occur in areas where weathering and erosion is accelerated.weathering and erosion is accelerated.

WeatheringWeathering is the disintegration and decomposition of rock at or near is the disintegration and decomposition of rock at or near the Earth’s surface by the Earth’s surface by mechanical, chemical, or biological mechanical, chemical, or biological weathering weathering processes.processes. Erosion Erosion is the removal and transportation of weathered or unweathered is the removal and transportation of weathered or unweathered materials by materials by water, wind, ice, and gravitywater, wind, ice, and gravity.. Mass-Wasting Mass-Wasting is a rapid period of weathering and erosion that removes is a rapid period of weathering and erosion that removes and transports materials very quickly and is often triggered by an and transports materials very quickly and is often triggered by an environmental stimuli. Mass wasting includesenvironmental stimuli. Mass wasting includes rock falls, landslides, rock falls, landslides, debris and mud flows, slumps, and creepdebris and mud flows, slumps, and creep..

Landforms formed by destructive processes include Landforms formed by destructive processes include river and river and stream valleys, waterfalls, glacial valleys, karst landscapes, stream valleys, waterfalls, glacial valleys, karst landscapes, coastal cliffs, and wave-cut scarps.coastal cliffs, and wave-cut scarps.

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Standard: 5-3.1

Genetic Landform ClassificationGenetic Landform Classification The genetic landform classification system groups landforms by The genetic landform classification system groups landforms by

the dominant set of geomorphic processes responsible for their the dominant set of geomorphic processes responsible for their formation. This includes the following processes and associated formation. This includes the following processes and associated landforms:landforms:

Tectonic LandformsTectonic Landforms Extrusive Igneous LandformsExtrusive Igneous Landforms Intrusive Igneous LandformsIntrusive Igneous Landforms Fluvial LandformsFluvial Landforms Karst LandformsKarst Landforms Aeolian LandformsAeolian Landforms Coastal LandformsCoastal Landforms Ocean Floor TopographyOcean Floor Topography Glacial LandformsGlacial Landforms

Within each of these genetic classifications, the resulting Within each of these genetic classifications, the resulting landforms are a product of either landforms are a product of either constructiveconstructive and and destructivedestructive processes processes or a combination of both.or a combination of both.

Landforms are also influenced by other agents or processes Landforms are also influenced by other agents or processes including time, climate, and human activity. including time, climate, and human activity.

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Tectonic LandformsTectonic Landforms Mountains: Orogenesis and DeformationMountains: Orogenesis and Deformation

FoldingFolding FaultingFaulting Fractures Fractures

Domes and BasinsDomes and Basins Horst and Graben Rift ValleysHorst and Graben Rift Valleys

Major Mountain Ranges:Major Mountain Ranges: Rocky MountainsRocky Mountains Appalachian MountainsAppalachian Mountains Himalayan MountainsHimalayan Mountains Andes MountainsAndes Mountains

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OrogenesisOrogenesis Orogenesis is the thickening of the continental crust and the Orogenesis is the thickening of the continental crust and the

building of mountains over millions of years and it translates from building of mountains over millions of years and it translates from Greek as “birth of mountains”, (Greek as “birth of mountains”, (oros oros is the Greek word for is the Greek word for mountain). mountain).

Orogeny encompasses all aspects of mountain formation including Orogeny encompasses all aspects of mountain formation including plate tectonics, terrane accretion, regional metamorphism, plate tectonics, terrane accretion, regional metamorphism, thrusting, folding, faulting, and igneous intrusions. thrusting, folding, faulting, and igneous intrusions.

Orogenesis is primarily covered in the plate tectonics section of Orogenesis is primarily covered in the plate tectonics section of the earth science education materials, but it is important to review the earth science education materials, but it is important to review for the landform section because it includes deformation for the landform section because it includes deformation processes responsible for mountain building. processes responsible for mountain building.

1818Photo courtesy of SCGS, SCDNRPhoto courtesy of SCGS, SCDNR

South Carolina’s Blue Ridge Mountains and Inner

Piedmont Region were formed by multiple orogenic events when rocks forming South

Carolina were uplifted, metamorphosed, folded,

faulted, and thrusted. More information on the Blue ridge mountains is included on the section for the Appalachian

Mountain Range.

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Standards: 3-3.6Standards: 5-3.1Standards: 8-3.7

DeformationDeformation Deformation processes deform or alter the earth’s crust by extreme stress or Deformation processes deform or alter the earth’s crust by extreme stress or

pressure in the crust and mantle. pressure in the crust and mantle.

Most deformation occurs along plate margins from plate tectonic movements. Most deformation occurs along plate margins from plate tectonic movements. Folding and faulting are the most common deformation processes.Folding and faulting are the most common deformation processes.

Folding Folding occurs when rocks are compressed such that the layers buckle and occurs when rocks are compressed such that the layers buckle and fold.fold.

FaultingFaulting occurs when rocks fracture under the accumulation of extreme stress occurs when rocks fracture under the accumulation of extreme stress created by compression and extensional forces. created by compression and extensional forces.

1919Photo: South Carolina Geological Survey Photo: South Carolina Geological Survey

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Both of these folds are in biotite-rich gneiss from the South Carolina Piedmont, the areas where the folds are most pronounced contain greater amounts of quartz from the granitic

composition of the rock. The scale card shows us that the rock on the left contains smaller folds than the rock on the right.

Standard: 8-3.7

FoldingFolding Folding occurs when rocks are compressed or deformed Folding occurs when rocks are compressed or deformed

and they buckle under the stress.and they buckle under the stress.

The diagram below is a cartoon illustrating how rocks fold.The diagram below is a cartoon illustrating how rocks fold.

The crest of the fold, where The crest of the fold, where the rock layers slope the rock layers slope downward form the downward form the anticline.anticline.

The valley of the fold where The valley of the fold where the layers slope toward the the layers slope toward the lower axis form the lower axis form the syncline. syncline.

2020

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Standard: 8-3.7

FoldingFolding Anticlines and synclines can take on slightly different geometries depending on Anticlines and synclines can take on slightly different geometries depending on

the compressional forces that form them.the compressional forces that form them.

Very intense compressional forces form tight isoclinal folds, less intense Very intense compressional forces form tight isoclinal folds, less intense compressional forces produce open folds. compressional forces produce open folds.

Folds can be asymmetric, upright, overturned, or curved. A fold pushed all the Folds can be asymmetric, upright, overturned, or curved. A fold pushed all the way over onto its side is called recumbent.way over onto its side is called recumbent.

Twisting or tilting during rock deformation and compression can cause folds to Twisting or tilting during rock deformation and compression can cause folds to form at different angles.form at different angles.

Some folds are very small and can be viewed in hand held specimens, while other Some folds are very small and can be viewed in hand held specimens, while other folds are as large as a mountain and can be viewed from aerial photos. folds are as large as a mountain and can be viewed from aerial photos.


Standard: 8-3.7

FoldingFolding

Copyright ©USGS

Anticline exposed along NJ Route 23 near Butler NJ. The man in the

bottom of the photo helps show the scale of the folds.

SCGS photo

Overturned folds in the Table Rock gneiss in South Carolina’s piedmont. The rock hammer in the photo is used

for scale.

Copyright ©Michael Lejeune

Syncline valley between mountain peaks.

Recumbent folds in limestone.

Copyright ©Marli Miller, University of Oregon


Standard: 3-3.6, 3-3.8Standard: 8-3.7, 8-3.9

FaultingFaulting Faulting occurs when the rocks fail under deformation processes. A fault is a planar discontinuity along which Faulting occurs when the rocks fail under deformation processes. A fault is a planar discontinuity along which

displacement of the rocks occurs.displacement of the rocks occurs. There are four basic types of faulting: normal, reverse, strike-slip, and oblique.There are four basic types of faulting: normal, reverse, strike-slip, and oblique.

Geologists recognize faults by looking for off-set rock layers in outcrops.Geologists recognize faults by looking for off-set rock layers in outcrops. Faults may also be recognized by debris, breccia, clay, or rock fragments that break apart or are pulverized Faults may also be recognized by debris, breccia, clay, or rock fragments that break apart or are pulverized

during the movement of the rocks along the fault plane. Fault ‘gouge’ is a term used to describe the material during the movement of the rocks along the fault plane. Fault ‘gouge’ is a term used to describe the material produced by faulting.produced by faulting.

If a fault plane is exposed, there may be grooves, striations (scratches), and slickenslides (symmetrical If a fault plane is exposed, there may be grooves, striations (scratches), and slickenslides (symmetrical fractures) that show evidence of the rocks movement.fractures) that show evidence of the rocks movement.

Large fault systems, such as the San Andreas fault can be seen from aerial imagery.Large fault systems, such as the San Andreas fault can be seen from aerial imagery.

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1. Normal: rocks above the fault plane, or hanging wall, move down relative to the rocks below the fault plane, or footwall.

2. Reverse: rocks above the hanging wall moves up relative to the footwall

3. Strike-slip: rocks on either side of a nearly vertical fault plane move horizontally

4. Oblique-slip: normal or reverse faults have some strike-slip movement, or when strike-slip faults have normal or reverse movement

Normal

Reverse

Strike-Slip

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Standard: 8-3.7

FaultingFaulting


Standard: 8-3.7

FaultingFaulting

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The San Andreas fault is the largest fault system in North America and it runs for nearly 780 miles through western California and in some places the width of the

fault zone is 60 miles. The San Andreas fault is a transform boundary between the Pacific Plate on the west and the North American Plate to the east. The

Pacific Plate is moving northwestward against the North American Plate. This motion generates earthquakes

along the fault that pose significant hazards to people and alters the physical landscape.

Offset in stream valley from San Andreas Fault movement Copyright © Michael Collier

These two faults are from South Carolina’s Piedmont. These faults are

evident by the off-set igneous intrusions in the rock.

Photo: South Carolina Geological Survey

Photo: South Carolina Geological Survey

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Fractures and JointsFractures and Joints Joints occur where a rock breaks but there is no displacement or faulting Joints occur where a rock breaks but there is no displacement or faulting

associated with the break. Joints are not singular features, but they occur in associated with the break. Joints are not singular features, but they occur in sets within a given type or area of a rock. sets within a given type or area of a rock.

Fractures are breaks in rocks that are often singular more random features and Fractures are breaks in rocks that are often singular more random features and are not associated with a set of joints. Fractures often occur in association with are not associated with a set of joints. Fractures often occur in association with faults or folds. faults or folds.

Crustal movements, deformation, or other tectonic related movements can Crustal movements, deformation, or other tectonic related movements can cause rocks to joint or fracture. cause rocks to joint or fracture.

Joints and fractures form from compression, tension, or shear stress and can Joints and fractures form from compression, tension, or shear stress and can range in size from millimeters to kilometers.range in size from millimeters to kilometers.

Common forms of jointing are columnar, sheet jointing, and tensional joints.Common forms of jointing are columnar, sheet jointing, and tensional joints. Columnar jointing Columnar jointing occurs when igneous rocks cool and develop shrinkage occurs when igneous rocks cool and develop shrinkage

joints along pillar-like columns. joints along pillar-like columns. Sheeting joints Sheeting joints occur when the layers of rock release pressure and exfoliate occur when the layers of rock release pressure and exfoliate

along parallel planes.along parallel planes. Brittle fractures and tensional joints Brittle fractures and tensional joints are caused by regionally extensive are caused by regionally extensive

compressional or elongated pressures along folds in the crustal rocks.compressional or elongated pressures along folds in the crustal rocks.

Sometimes, jointing is obvious, but the processes that caused it may be Sometimes, jointing is obvious, but the processes that caused it may be unknown, or difficult to identify. unknown, or difficult to identify.

Fractures and joints create a variety of pathways for water to flow through, Fractures and joints create a variety of pathways for water to flow through, which weaken the rock and facilitate chemical, biological, and mechanical which weaken the rock and facilitate chemical, biological, and mechanical weathering processes.weathering processes.

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Standard: 8-3.7

JointingJointing

These two images are an example of columnar jointing. The image on the top is a side view and the image below is from the

top. These hexagonal columns of rock formed from cooled basalt are part of Devil’s Postpile National Monument in

California.

2727

The image below is of vertical jointed, bedded meta-sandstone in the Snake Range

in Nevada.

Copyright Larry Fellows, Arizona Geological Survey

Copyright © Bruce Molnia, USGS

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Domes and BasinsDomes and Basins Domes and basins are large, elongated folds formed by broad warping Domes and basins are large, elongated folds formed by broad warping

processes including mantle convection, isostatic adjustment, or swelling processes including mantle convection, isostatic adjustment, or swelling from a hot spot. from a hot spot.

Upwarping produces domes, while downwarping produces basins. Upwarping produces domes, while downwarping produces basins. Geologists identify dome and basin structures by the stratified ages of the Geologists identify dome and basin structures by the stratified ages of the

rock folds:rock folds: Domes contain strata which increase in age toward the center as the contain strata which increase in age toward the center as the

younger layers are eroded from the top and sides.younger layers are eroded from the top and sides. Basins contain strata which is youngest toward the center and the contain strata which is youngest toward the center and the

oldest rocks form the flanks or sides. oldest rocks form the flanks or sides.

2828http://en.wikipedia.org/wiki/Michigan_Basin

This geologic map of the Michigan Basin illustrates the circular pattern of

the sedimentary strata. The green color in the center of the map

represents the youngest rocks which are Upper Pennsylvanian; and the

rocks progressively increase in age toward the periphery where the

reddish-orange colors represent the oldest rocks flanking this structure which are Ordovician and Cambrian

age.

Youngest rocks (Upper Pennsylvanian)

Oldest Rocks (Ordivician and Cambrian)

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Standards: 8-3.7, 8-3.9

Horst and Graben: Horst and Graben: Basin and RangeBasin and Range

Horst and graben topography is generated by normal faulting associated with Horst and graben topography is generated by normal faulting associated with crustal extension. crustal extension.

The central block termed graben is bounded by normal faults and the graben The central block termed graben is bounded by normal faults and the graben drops as the crust separates. drops as the crust separates.

The graben forms an elongated valley that is bound by uplifted ridge-like The graben forms an elongated valley that is bound by uplifted ridge-like mountainous structures referred to as horsts. mountainous structures referred to as horsts.

Some horsts may tilt slightly producing asymmetric, tilted terrane or Some horsts may tilt slightly producing asymmetric, tilted terrane or mountain ranges. mountain ranges.

In the Western United States, horst and graben fault sequences are described In the Western United States, horst and graben fault sequences are described as “Basin and Range” topography. as “Basin and Range” topography.

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Basin and Range topography, Nevada.Basin and Range topography, Nevada.

Copyright © Marli Miller, University of Oregon

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Standards: 5-3.1Standards: 8-3.7, 8-3.9

Rift ValleysRift Valleys Rift valleys are fault structures formed by normal faults.Rift valleys are fault structures formed by normal faults. Rising magma below the crust upwells, forcing the lithosphere to fracture, Rising magma below the crust upwells, forcing the lithosphere to fracture,

as it fractures and cracks, one or more faults cause the crustal rocks to as it fractures and cracks, one or more faults cause the crustal rocks to separate forming a rift valley. separate forming a rift valley.

Rift valleys can eventually form lakes or seas such as the Red Sea, which Rift valleys can eventually form lakes or seas such as the Red Sea, which separates Africa from the Arabian Peninsula. Rift valleys can become separates Africa from the Arabian Peninsula. Rift valleys can become inactive and fill in with volcanic material, such as the rift structure in the inactive and fill in with volcanic material, such as the rift structure in the United States which extends from Lake Superior to Oklahoma. United States which extends from Lake Superior to Oklahoma.

3030www.visibleearth.nasa.gov

East African Rift Valley LakeRift Valleys in Africa

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Standards: 5-3.1, 5-3.2Standards: 8-3.7, 8-3.9

Major Mountain Ranges of the Major Mountain Ranges of the WorldWorld

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Antarctica: Antarctic Peninsula, Transantarctic MountainsAntarctica: Antarctic Peninsula, Transantarctic Mountains Africa: Atlas, Eastern African Highlands, Ethiopian HighlandsAfrica: Atlas, Eastern African Highlands, Ethiopian Highlands Asian: Himalayas, Taurus, Elburz, Japanese MountainsAsian: Himalayas, Taurus, Elburz, Japanese Mountains Australia: MacDonnell MountainsAustralia: MacDonnell Mountains Europe: Pyrenees, Alps, Carpathians, Apennines, Urals, Balkan Europe: Pyrenees, Alps, Carpathians, Apennines, Urals, Balkan

MountainsMountains North American: Appalachians, Sierra Nevada, Rocky Mountains, North American: Appalachians, Sierra Nevada, Rocky Mountains,

LaurentidesLaurentides South American: Andes, Brazilian HighlandsSouth American: Andes, Brazilian Highlands

Rocky Rocky MountainsMountains

AndesAndesMountaiMountai

nsns

AppalachianAppalachianMountainsMountains

HimalayaHimalayaMountainsMountains

European AlpsEuropean Alps

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Standards: 3-3.6Standards: 8-3.9

Rocky MountainsRocky Mountains The Rocky Mountains, which extend from British Columbia to Texas were The Rocky Mountains, which extend from British Columbia to Texas were

formed by the Laramide Orogeny 40-80 million years ago; however, there is formed by the Laramide Orogeny 40-80 million years ago; however, there is still active uplift today.still active uplift today.

Colorado’s Front Range, the Sangre de Cristo Mountains of Colorado and New Colorado’s Front Range, the Sangre de Cristo Mountains of Colorado and New Mexico, the Franklin Mountains in Texas, and Wyoming’s Bighorn Mountains Mexico, the Franklin Mountains in Texas, and Wyoming’s Bighorn Mountains are all part of the “Rocky Mountain Range”.are all part of the “Rocky Mountain Range”.

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The Laramide Orogeny was characterized by intense tectonic activity resulting from a series of

compressional and extensional events. The subduction of the Pacific Ocean Plate caused

compressional forces in the continental plate, and pushed the oceanic plate downward. Following subduction of the oceanic plate, upwelling and

extensional forces caused the literal uplift of the continental bedrock and formed of the Rocky Mountains. The lower crust in this region of upwelling and uplifting is relatively thin and

stretches under pressure. The upper crust is very brittle and deforms easily. As a result the upper

crust is characterized by large angular tilted faults blocks which form the Rocky Mountains we see

today.

Source: USGS

The Rocky Mountains contain some of the most beautiful scenery in North America and are home to hundreds of parks and

recreational areas including Rocky Mountain National Park, Yosemite National

Park, Glacier National Park, and Grand Tetons National Park.

Copyright© Dr. Roger Slatt, University of Oklahoma

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Standards: 3-3.6Standards: 5-3.1Standards: 8-3.7, 8-3.9

Appalachian MountainsAppalachian Mountains The Appalachian Mountains extend along the eastern margin of North America The Appalachian Mountains extend along the eastern margin of North America

from Alabama to Maine in the United States, and through the southeastern from Alabama to Maine in the United States, and through the southeastern provinces of Canada to Newfoundland. provinces of Canada to Newfoundland.

The Appalachian Mountains were formed during the Paleozoic Era from several The Appalachian Mountains were formed during the Paleozoic Era from several orogenic episodes, the Taconic Orogeny (Ordovician ~480 mya), followed by the orogenic episodes, the Taconic Orogeny (Ordovician ~480 mya), followed by the Acadian Orogeny (Devonian ~400 mya), and lastly the Alleghany Orogeny Acadian Orogeny (Devonian ~400 mya), and lastly the Alleghany Orogeny (Permian ~ 300 mya). (Permian ~ 300 mya).

Each of these major orogenic episodes involved multiple events of folding, Each of these major orogenic episodes involved multiple events of folding, faulting, metamorphism, emplacements of igneous intrusions, and uplift.faulting, metamorphism, emplacements of igneous intrusions, and uplift.

The Appalachian Mountains are divided into four major provinces: Piedmont, Blue The Appalachian Mountains are divided into four major provinces: Piedmont, Blue Ridge, Valley and Ridge, and Appalachian Plateau. Ridge, Valley and Ridge, and Appalachian Plateau.

3333Source: USGS

This is an aerial view of the Susquehanna River in Pennsylvania flowing through the folded and faulted Valley and Ridge Province of the Appalachian Mountains.

Waterfall carved into valley of Blue Ridge

Province of the Appalachians near the

South Carolina and North Carolina border.

Source: SCGS

www. maps.google.com

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Andes MountainsAndes Mountains The Andes Mountains began forming during the Jurrasic period (~200 mya) The Andes Mountains began forming during the Jurrasic period (~200 mya)

when plate tectonics forced the oceanic Nazca plate to subduct beneath the when plate tectonics forced the oceanic Nazca plate to subduct beneath the continental South American plate.continental South American plate.

The subduction zone between the plate margins marks the Peru-Chile ocean The subduction zone between the plate margins marks the Peru-Chile ocean trench which is 26,500 ft (8,065 meters) below sea level.trench which is 26,500 ft (8,065 meters) below sea level.

Tectonic forces along this active continental margin are forcing the ongoing Tectonic forces along this active continental margin are forcing the ongoing uplift, folding, faulting, and thrusting of bedrock forming the Andes Mountains. uplift, folding, faulting, and thrusting of bedrock forming the Andes Mountains.

The Andes are the longest mountain range on land and they extend along the The Andes are the longest mountain range on land and they extend along the entire western coast of South America. They are divide into three sections: (1) entire western coast of South America. They are divide into three sections: (1) Southern Andes in Argentina and Chile, (2) Central Andes including the Chilean Southern Andes in Argentina and Chile, (2) Central Andes including the Chilean and Peruvian cordilleras an parts of Bolivia, and (3) Northern sections in and Peruvian cordilleras an parts of Bolivia, and (3) Northern sections in Venezuela, Columbia, and Ecuador, including to parallel ranges the Cordillera Venezuela, Columbia, and Ecuador, including to parallel ranges the Cordillera Occidental and the Cordillera Oriental.Occidental and the Cordillera Oriental.

The Andes Mountains contain many active volcanoes, including Cotopaxi in The Andes Mountains contain many active volcanoes, including Cotopaxi in Ecuador, one of the largest active volcanoes in the world. Ecuador, one of the largest active volcanoes in the world.

3434http:visibleearth.nasa.gov/

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European AlpsEuropean Alps The European Alps began forming during the Alpine Orogeny (~ 20-120 mya) The European Alps began forming during the Alpine Orogeny (~ 20-120 mya)

with the collision of the African Plate moving northward into the European Plate. with the collision of the African Plate moving northward into the European Plate. This motion is still active today as the Alps continue to uplift, fold, fault, and This motion is still active today as the Alps continue to uplift, fold, fault, and accrete.accrete.

The Alps are the largest mountain range in Europe and they extend from Austria The Alps are the largest mountain range in Europe and they extend from Austria and Slovenia in the east, through Italy, Switzerland, Germany, and France in the and Slovenia in the east, through Italy, Switzerland, Germany, and France in the west.west.

Major orogenic events involved recumbent folding and thrust faulting of Major orogenic events involved recumbent folding and thrust faulting of crystalline basement rocks that today form some of the highest peaks in the crystalline basement rocks that today form some of the highest peaks in the Alps.Alps.

The Alps were one of the first mountain ranges to be studied by geologists and The Alps were one of the first mountain ranges to be studied by geologists and as a result many geomorphic terms, especially those relating to glaciation and as a result many geomorphic terms, especially those relating to glaciation and ‘alpine’ environments, were first defined in the European Alps. ‘alpine’ environments, were first defined in the European Alps.

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The Matterhorn, on the border between Switzerland an Italy, is one of the most familiar mountains in the world and is a

popular climbing site. The continent-continent collision resulted in the peak of

the Matterhorn containing bedrock from the African Plate while the lower portions

contain bedrock from the European Plate.

http://en.wikipedia.org/wiki/Matterhorn

SwitzerlandSwitzerland

ItalyItalyFranceFrance

GermanyGermany AustriaAustria

SloveniSloveniaaE u r o

p e a n A l p

s

Modified from: http://en.wikipedia.org/wiki/AlpsTable of Contents

African Plate

European Plate


Himalaya MountainsHimalaya Mountains Himalaya orogeny began 45-54 million years ago from the collision between Himalaya orogeny began 45-54 million years ago from the collision between

the India and Eurasian Plates and is still active today. the India and Eurasian Plates and is still active today. When two continental plates collide, the Earth’s crust at the plate When two continental plates collide, the Earth’s crust at the plate

boundaries is folded, faulted, overthrusted, uplifted forming an extensive boundaries is folded, faulted, overthrusted, uplifted forming an extensive continental mountain range.continental mountain range.

Today, the Himalayas separate the Indian sub-continent from the Tibetan Today, the Himalayas separate the Indian sub-continent from the Tibetan Plateau and they are recognized as the tallest above sea level mountains on Plateau and they are recognized as the tallest above sea level mountains on Earth. The Himalayas contain 10 of the tallest mountain peaks on Earth Earth. The Himalayas contain 10 of the tallest mountain peaks on Earth >8,000 meters , including Mount Everest with a peak of 8850 meters (29,035 >8,000 meters , including Mount Everest with a peak of 8850 meters (29,035 ft). In addition, the Himalayas include three major individual mountain ft). In addition, the Himalayas include three major individual mountain ranges, the Karakoram, Hindu Kush, and Toba Kakar.ranges, the Karakoram, Hindu Kush, and Toba Kakar.

Shallow, intermediate, and deep earthquakes are associated with this zone, Shallow, intermediate, and deep earthquakes are associated with this zone, and scientists predict that several major earthquakes will occur in the region and scientists predict that several major earthquakes will occur in the region posing a significant hazard to millions of people. posing a significant hazard to millions of people.

3636

The name Himalaya is from Sanskirt, and it means “the abode

of snow”. ‘Hima’ for snow and ‘alaya’ for abode.

www.usgs.govhttp://en.wikipedia.org/wiki/Image:Himalayas.jpg

Continental – Continental Plate Collision

Table of Contents


Volcanic Landforms: Volcanic Landforms: Extrusive IgneousExtrusive Igneous

Cinder ConesCinder Cones Shield VolcanoesShield Volcanoes Strato (Composite)VolcanoesStrato (Composite)Volcanoes Lava DomesLava Domes CalderaCaldera Volcanic NecksVolcanic Necks Volcanic Hot-SpotsVolcanic Hot-Spots


Standards: 3-3.6, 3-3.8Standards: 5-3.1Standards: 8-3.7

Cinder ConesCinder Cones Cinder cones are relatively small cone shaped hills (< 2000 ft of relief) formed by the

accumulation of cinders and ash during volcanic eruptions. The cinders form from bursting bubbles of gas in the magma that eject lava into the air. The summit my be truncated or bowl-shaped where the magma emerges from a single central vent or volcanic neck.

Cinder cones are formed from an accumulation of ejected tephra and scoria rocks. Tephra and scoria occur in a range of different sizes from fine ashes to large volcanic rock fragments. Once the magma is ejected into the air, it cools, hardens, and is deposited on the summit or slopes of the cinder cone. The pyroclastic tephra and scoria rocks are produced from gas-rich basaltic magma, and is usually reddish-brown to black in color.

Cinder cones generally form from a single volcanic episode and are rarely associated with eruptions lasting more than a decade.

Cinder cones can be found in combination with shield and strato volcanos and can occur at convergent or divergent plate boundaries.

Cinder cones are the most common type of volcano and often occur in large numbers within a region forming ‘volcano fields’. Flagstaff Arizona contains a volcanic field of nearly 600 cinder cones.

Cinder cones have an easily recognizable hill shape form with relatively steep 30-40 degree slopes. This angle

represents the steepest angle maintained by unconsolidated,

loose material and is commonly referred to as the

angle of repose. This image is of an older cinder cone with small caldera depression on

the summit.Copyright © Larry Fellows, USGS

3838

Standards: 3-3.6, 3-3.8Standards: 5-3.1Standards: 8-3.7, 8-3.9

Table of Contents

Shield VolcanoesShield Volcanoes Shield volcanoes are broad shaped mountain landforms built by the accumulation of Shield volcanoes are broad shaped mountain landforms built by the accumulation of

fluid basaltic lava. Their slopes are often very gentle and may be < 5 degrees, and fluid basaltic lava. Their slopes are often very gentle and may be < 5 degrees, and their summits, or peaks, are relatively flat. They received their name because their their summits, or peaks, are relatively flat. They received their name because their gently domed form resembles the exterior of a warrior’s shield. gently domed form resembles the exterior of a warrior’s shield.

Most shield volcanoes originate from the ocean floor and have ‘grown’ to form islands Most shield volcanoes originate from the ocean floor and have ‘grown’ to form islands or seamounts. Hawaii and the Galapagos Islands are examples of shield volcanoes or seamounts. Hawaii and the Galapagos Islands are examples of shield volcanoes that formed in the ocean and emerged as mountainous, island landforms. that formed in the ocean and emerged as mountainous, island landforms.

Magma, or lava, discharges from both the summit and rifts along the slopes. Most Magma, or lava, discharges from both the summit and rifts along the slopes. Most lava that forms shield volcanoes erupts as a flow from fissures; however, occasional lava that forms shield volcanoes erupts as a flow from fissures; however, occasional high intensity pyroclastic ejections may occur. high intensity pyroclastic ejections may occur.

Shield volcanoes usually have either smooth, ropy pahoehoe lava, or blocky, Shield volcanoes usually have either smooth, ropy pahoehoe lava, or blocky, sharp aa lava.

Shield volcanoes form the largest volcanoes on Earth.

Photo: D. Little, USGS

Mauna Loa Volcano on Hawaii is a shield volcano and the lava flow below

illustrates a typical eruption for a shield volcano.

Courtesy USGS Hawaiian Volcano Observatory

3939


Table of Contents

Strato VolcanoesStrato Volcanoes Strato-volcanoes, also referred to as composite cones, are large, nearly symmetrical Strato-volcanoes, also referred to as composite cones, are large, nearly symmetrical

mountainous landforms, formed by a combination of lava flows and intense mountainous landforms, formed by a combination of lava flows and intense pyroclastic eruptions. pyroclastic eruptions.

Eruptions are violent and the ejected material is primarily a gas-rich, high viscosity Eruptions are violent and the ejected material is primarily a gas-rich, high viscosity (resistance to flow) magma with an andesitic composition. Eruptions can also (resistance to flow) magma with an andesitic composition. Eruptions can also produce extensive ash deposits. produce extensive ash deposits.

Most strato volcanoes are located along the Most strato volcanoes are located along the ring of fire ring of fire which is a geographic zone which is a geographic zone that rims the Pacific Plate where it is in contact with the Eurasian, North American, that rims the Pacific Plate where it is in contact with the Eurasian, North American, and Indo-Australian Plate. and Indo-Australian Plate.

Well-known strato volcanoes occur in the Andes, the Cascade Range of the United Well-known strato volcanoes occur in the Andes, the Cascade Range of the United States and Canada (including Mount St. Helens, Mount Ranier, and Mount Garibaldi), States and Canada (including Mount St. Helens, Mount Ranier, and Mount Garibaldi), and the volcanic islands of the western Pacific from the Aleutian Islands to Japan, the and the volcanic islands of the western Pacific from the Aleutian Islands to Japan, the Philippines, and New Zealand. Philippines, and New Zealand.

USGS Cascades Volcano Observatory

Mount St. Helens 1980 eruption

4040


Table of Contents

Kimberly Meitzen

Need Map of ring of fire

CalderaCaldera Calderas are bowl-shaped collapse depressions formed by volcanic processes. Calderas are bowl-shaped collapse depressions formed by volcanic processes. Calderas most likely result from one of three collapse type events: Calderas most likely result from one of three collapse type events:

1. Collapse of the summit following an explosive eruption of silica-rich pumice and ash 1. Collapse of the summit following an explosive eruption of silica-rich pumice and ash pyroclastics pyroclastics

2. Collapse of the summit following the subterranean or fissure drainage of the magma chamber2. Collapse of the summit following the subterranean or fissure drainage of the magma chamber 3. Collapse of a large area following the discharge of silica-rich pumice and ash along ring 3. Collapse of a large area following the discharge of silica-rich pumice and ash along ring

fractures that may or may not have been previously active volcanoesfractures that may or may not have been previously active volcanoes Crater Lake in Oregon is an example of a 700 year old caldera that formed from the Crater Lake in Oregon is an example of a 700 year old caldera that formed from the

eruption and collapse of Mount Mazama. Today it is filed in with rainwater and forms a eruption and collapse of Mount Mazama. Today it is filed in with rainwater and forms a lake. A small cinder cone, named Wizard Island, formed inside the caldera and today it lake. A small cinder cone, named Wizard Island, formed inside the caldera and today it emerges as an island in the lake.emerges as an island in the lake.

Many of the calderas on Hawaiian volcanoes formed after the magma drained through Many of the calderas on Hawaiian volcanoes formed after the magma drained through fissures in the central magma chamber and the summit eventually collapses.fissures in the central magma chamber and the summit eventually collapses.

Yellowstone National Park contains a caldera that is >43 miles across and was formed Yellowstone National Park contains a caldera that is >43 miles across and was formed by an intense pyroclastic eruption that ejected ash fragments as far as the gulf of by an intense pyroclastic eruption that ejected ash fragments as far as the gulf of Mexico.Mexico.

4141

Crater Lake in Oregon is the collapsed caldera of Mount Mazama and

is now filled in with water. Wizard Island is a volcanic cone in the

middle of the lake. Crater Lake is the

deepest lake in the United States at 1,932

feet deep! Copyright Larry Fellows, USGS


Table of Contents

Lava DomesLava Domes Lava domes are rounded, steep-sided mounds built by very viscous Lava domes are rounded, steep-sided mounds built by very viscous

magma that is resistant to flow and builds up forming a dome. magma that is resistant to flow and builds up forming a dome. The magma does not move far from the vent before cooling and it The magma does not move far from the vent before cooling and it

crystallizes in very rough, angular basaltic rocks. crystallizes in very rough, angular basaltic rocks. A single lava dome may be formed by multiple lava flows that accumulate A single lava dome may be formed by multiple lava flows that accumulate

over time.over time.

4242Copyright©Lyn Topinka

This lava dome began forming after the Mount St. Helen’s eruption in 1980.

Geologists set up a monitoring station to measure the growth of this lava dome and

recorded that it is growing at a rate of about 40 feet per year.


Table of Contents

Volcanic Hot SpotsVolcanic Hot Spots Volcanic hot-spots occur where a mass of magma ascends toward the earth’s surface as a Volcanic hot-spots occur where a mass of magma ascends toward the earth’s surface as a

mantle plume, releasing basaltic magma that generates volcanic activity at a locally mantle plume, releasing basaltic magma that generates volcanic activity at a locally specific site.specific site.

Hot-spots do not occur along plate boundaries but instead form as intraplate volcanic Hot-spots do not occur along plate boundaries but instead form as intraplate volcanic features characterized by magma upwelling. Once a hot spot is generated it may stay features characterized by magma upwelling. Once a hot spot is generated it may stay active for millions of years. active for millions of years.

Hot spots may produce thermal effects in the ground water and the crust producing Hot spots may produce thermal effects in the ground water and the crust producing geothermal power often in the form of steam. In Iceland and Italy geothermal power is geothermal power often in the form of steam. In Iceland and Italy geothermal power is used to generate electricity for industrial and municipal use.used to generate electricity for industrial and municipal use.

The Hawaiian Islands formed over the last 5 million years from a hot spot in the Pacific The Hawaiian Islands formed over the last 5 million years from a hot spot in the Pacific Ocean. As the Pacific plate moves over the hotspot, it generates a chain of islands that Ocean. As the Pacific plate moves over the hotspot, it generates a chain of islands that emerge as seamounts above the ocean’s surface. Hot spot activity is currently most active emerge as seamounts above the ocean’s surface. Hot spot activity is currently most active on the big island, Hawaii. on the big island, Hawaii.

4343

KauaiOahu

Maui

HawaiiKahoolawe

Lanai

Molokai

Nihau

Pacific Plate Movement

Oldest IslandsOldest Islands

Youngest IslandsYoungest Islands www.usgs.gov

www.maps.google.com


Table of Contents

Volcanic NecksVolcanic Necks

Volcanic necks are remnant cooled lava pipes that are exposed after the Volcanic necks are remnant cooled lava pipes that are exposed after the exterior volcanic mountain is weathered and eroded. exterior volcanic mountain is weathered and eroded.

Volcanic necks are a good example of differential weathering. The magma Volcanic necks are a good example of differential weathering. The magma cooled in the interior pipes is more resistant than the ejected deposits that cooled in the interior pipes is more resistant than the ejected deposits that accumulate on the exterior. As a result, when the volcanic mountain erodes, accumulate on the exterior. As a result, when the volcanic mountain erodes, it leaves behind the remnant more resistant volcanic neck. it leaves behind the remnant more resistant volcanic neck.

4444

Shiprock is a volcanic neck of a solidified lava core from a dormant

40-million year old volcano. Its elevation is 7,178 feet above sea

level with a local relief of 1,800 feet. It lies southwest of the town of Shiprock, New Mexico, and was

named after 19th -century clipper ships.

Copyright © Michael Collier


Table of Contents

Flood BasaltsFlood Basalts Flood basalts, also referred to as plateau basalts, are massive Flood basalts, also referred to as plateau basalts, are massive

accumulations of basaltic lava that are molten enough to flow for miles accumulations of basaltic lava that are molten enough to flow for miles before cooling.before cooling.

Flood basalts form from lava released from fissures in the crust, and are Flood basalts form from lava released from fissures in the crust, and are not produced by classic volcanic mountain-related eruptions.not produced by classic volcanic mountain-related eruptions.

The Columbia Plateau in northwest United States was formed when The Columbia Plateau in northwest United States was formed when multiple fissures released successive lava flows producing regionally multiple fissures released successive lava flows producing regionally extensive flood basalts.extensive flood basalts.

4545Photo courtesy: Stephen Riedel

The Columbia River Flood Basalt Province spans Idaho, Washington, and Oregon in the United States. The flood- basalt plateaus were

formed by multiple extensive lava flows that accumulated over millions of years. Today the

landscape is dissected by rivers and valleys and the individual layers of

basalts are exposed. This image shows two major basalt layers, the

Grande Basalt and the Imnahu Basalt.


Table of Contents

Volcanic Landforms: Volcanic Landforms: Intrusive IgneousIntrusive Igneous

Batholiths Batholiths Plutons Plutons Stocks Stocks MonadnocksMonadnocks LaccolithsLaccoliths DikesDikes SillsSills VeinsVeins

4646

Source: USGS

Standards: 3-3.6, 3-3.8Standards: 5-3.1Standards: 8-3.7

Table of Contents

BatholithBatholith Batholiths are massive igneous intrusions that form linear bodies that extend for Batholiths are massive igneous intrusions that form linear bodies that extend for

hundreds of kilometers across the landscape and can be several kilometers thick.hundreds of kilometers across the landscape and can be several kilometers thick. Some batholiths may incorporate groups of smaller plutons in addition to their massive Some batholiths may incorporate groups of smaller plutons in addition to their massive

structure.structure. Batholiths form below the earth’s surface as intrusions of magma emplaced during Batholiths form below the earth’s surface as intrusions of magma emplaced during

tectonic processes. Following emplacement they may be uplifted and exposed by tectonic processes. Following emplacement they may be uplifted and exposed by weathering and erosion processes. weathering and erosion processes.

Some batholiths are metamorphosed by heat and pressure. For example, many of the Some batholiths are metamorphosed by heat and pressure. For example, many of the batholiths in the Appalachian Mountains are metamorphosed igneous intrusions. batholiths in the Appalachian Mountains are metamorphosed igneous intrusions.

4747

Half Dome is a granitic igneous intrusion that forms an impressive mountain peak that is part of the greater Sierra Nevada Batholith in Yosemite National Park. The ‘Half

Dome’ shape was carved by glacial erosion. The Sierra Nevada Batholith,

which includes Half Dome, Mt. Whitney, and El Capitan, became

exposed as the mountains uplifted and weathering and erosion removed the material surrounding the batholith.

Copyright © Bruce Molnia at Terra Photographics


Table of Contents

PlutonsPlutons Plutons are intrusive igneous rocks which form below the Earth’s surface and are Plutons are intrusive igneous rocks which form below the Earth’s surface and are

surrounded by sedimentary or metamorphic rocks. surrounded by sedimentary or metamorphic rocks. Plutons are formed as magma forces its way up through other rocks and solidifies Plutons are formed as magma forces its way up through other rocks and solidifies

before reaching the surface. before reaching the surface. Some plutons are remnant magma chambers that once fueled volcanic activity.Some plutons are remnant magma chambers that once fueled volcanic activity. Plutons become exposed on the landscape as the other rocks surrounding them are Plutons become exposed on the landscape as the other rocks surrounding them are

removed by weathering and erosion. removed by weathering and erosion. Some plutons appear as small or large hills while others appear as tabular, flat rock Some plutons appear as small or large hills while others appear as tabular, flat rock

exposures. exposures.

4848

Enchanted Rock is a large granitic pluton in the Llano Uplift of the Texas Hill Country Region that is part of a larger igneous

batholith.

http://en.wikipedia.org/wiki/Image:Enchanted_rock_2006.jpg


Table of Contents

Sills, Laccoliths, and DikesSills, Laccoliths, and Dikes Sills and laccoliths are igneous intrusions that form near the earth’s surface. They Sills and laccoliths are igneous intrusions that form near the earth’s surface. They

are concordant features meaning that they form parallel to existing strata or are concordant features meaning that they form parallel to existing strata or structures. structures.

Sills form near the surface from very fluid magma that cools quickly they are usually Sills form near the surface from very fluid magma that cools quickly they are usually mostly basaltic rocks with an aphanitic (fine-grained) texture.mostly basaltic rocks with an aphanitic (fine-grained) texture.

Laccoliths are similar to sills, accept they are formed by more viscous magma which Laccoliths are similar to sills, accept they are formed by more viscous magma which collects in a lens shape prior to cooling as a concordant igneous intrusion near the collects in a lens shape prior to cooling as a concordant igneous intrusion near the surface. This process may force the overlaying strata to form a slightly domed surface. This process may force the overlaying strata to form a slightly domed structure over the bulging laccolith. structure over the bulging laccolith.

Dikes are tabular intrusions of igneous rock that form when magma injects into Dikes are tabular intrusions of igneous rock that form when magma injects into fractures. Dikes are discordant features, meaning that they cut through layers of fractures. Dikes are discordant features, meaning that they cut through layers of rock. rock.

Magma can force the rock apart separating the fracture. Magma can force the rock apart separating the fracture. The cooled magma can range in thickness from centimeters to kilometers and may The cooled magma can range in thickness from centimeters to kilometers and may

be more resistant to erosion than the surrounding rocks enabling them to protrude be more resistant to erosion than the surrounding rocks enabling them to protrude outward amidst their surroundings.outward amidst their surroundings.

4949Copyright ©Michael Collier

Salisbury Craig is an exposed sill north of Edinburg, Scotland that

forms a resistant cap on this hill top.

http://en.wikipedia.org/wiki/sill

The dark linear feature in this

image is an exposed dike that is more resistant to

weathering and erosion than the

surrounding landscape.


Table of Contents

MonadnocksMonadnocks Monadnocks are large hills or mountains of bedrock that stand out in the Monadnocks are large hills or mountains of bedrock that stand out in the

landscape. landscape. Monadnocks persist in the landscape because they consist of a more resistant Monadnocks persist in the landscape because they consist of a more resistant

rock material than the surrounding rock types which have been weathered and rock material than the surrounding rock types which have been weathered and eroded away.eroded away.

In South Carolina, most monadnocks consist primarily of metamorphosed In South Carolina, most monadnocks consist primarily of metamorphosed igneous intrusions, which are more resistant to weathering than the igneous intrusions, which are more resistant to weathering than the surrounding rocks. Little Mountain, Table Rock, Caesar’s Head, and Glassy surrounding rocks. Little Mountain, Table Rock, Caesar’s Head, and Glassy Mountain, are all examples of monadnocks in South Carolina.Mountain, are all examples of monadnocks in South Carolina.

5050

Source: SCGS

Table Rock in South Carolina is an example of a monadnock

landform. It’s geologic history indicates that is was emplaced as an igneous intrusion during the Paleozoic, and it was later

metamorphosed during the building of the Appalachian

Mountains. Millions of years of weathering and erosion of the surrounding rock have enabled

Table Rock to persist as a resistant outcrop at the edge of

South Carolina’s Piedmont.


Table of Contents

River Systems and Fluvial River Systems and Fluvial LandformsLandforms

River Systems and Fluvial LandformsRiver Systems and Fluvial Landforms Longitudinal Profile and WatershedsLongitudinal Profile and Watersheds South Carolina RiversSouth Carolina Rivers Lakes and DamsLakes and Dams Mountain StreamsMountain Streams Straight RiversStraight Rivers Braided RiversBraided Rivers Meandering RiversMeandering Rivers Anabranching RiversAnabranching Rivers GulleysGulleys River TerracesRiver Terraces River CanyonsRiver Canyons WaterfallsWaterfalls Flood plainsFlood plains Alluvial FansAlluvial Fans

5151

The Congaree River in South Carolina is home to Congaree National Park which is a large flood plain

ecosystem that protects some of the oldest and largest bottomland hardwood forests in the nation.

Almost every year the Congaree River floods the National Park providing water, sediments, and

nutrients that support the incredible growth of the forest and rich biodiversity of organisms.

Photo: SCGS

Standards: 3-3.5, 3-3.6, 3-3.8Standards: 5-3.1Standards: 8-3.7, 8-3.9

Table of Contents

River Systems and Fluvial River Systems and Fluvial ProcessesProcesses

Rivers are one of the most dominant agents of landscape change because their flowing Rivers are one of the most dominant agents of landscape change because their flowing waters are continually eroding, transporting, and depositing sediments. waters are continually eroding, transporting, and depositing sediments.

Rivers are critically important to people because they provide fresh drinking water, Rivers are critically important to people because they provide fresh drinking water, transportation of people, goods, and wastes, hydro-electric power generation, irrigation, transportation of people, goods, and wastes, hydro-electric power generation, irrigation, and recreation. and recreation.

Rivers, although very important to people, are also very dangerous because flooding is Rivers, although very important to people, are also very dangerous because flooding is among one of the most frequent and widespread natural hazards that can damage or among one of the most frequent and widespread natural hazards that can damage or destroy land, property, and life.destroy land, property, and life.

Because rivers systems are so important to humans, it is necessary for scientists to Because rivers systems are so important to humans, it is necessary for scientists to understand how rivers affect the landscape and also how humans affects rivers. Having understand how rivers affect the landscape and also how humans affects rivers. Having this information enables people to better manage for future water resource needs and this information enables people to better manage for future water resource needs and prevent hazardous situations.prevent hazardous situations.

5252Image Source: SCGS


Table of Contents

Longitudinal Profile and Longitudinal Profile and WatershedsWatersheds

The The longitudinal profile longitudinal profile of a river is an elevation cross-section of the entire watershed of a river is an elevation cross-section of the entire watershed from the source of flowing water to the mouth of the stream. from the source of flowing water to the mouth of the stream.

The source area of flowing water is defined as the The source area of flowing water is defined as the headwatersheadwaters. Headwaters are the . Headwaters are the highest elevation where water collects to form a stream network and is generally highest elevation where water collects to form a stream network and is generally formed by either snow-melt runoff, a natural spring, or rainwater. formed by either snow-melt runoff, a natural spring, or rainwater.

The mouth of the stream is typically defined by the stream’s ultimate The mouth of the stream is typically defined by the stream’s ultimate base levelbase level, and , and this generally corresponds with the sea level where the river meets the ocean. Base this generally corresponds with the sea level where the river meets the ocean. Base level is the lowest elevation that a stream can erode its channel. Local or temporary level is the lowest elevation that a stream can erode its channel. Local or temporary base levels may be formed by reservoirs or waterfalls. base levels may be formed by reservoirs or waterfalls.

A river’s gradient (slope) is steepest near the headwaters and gentlest near the A river’s gradient (slope) is steepest near the headwaters and gentlest near the mouth.mouth.

As rivers flow from their headwaters to their base level they carve valleys into the As rivers flow from their headwaters to their base level they carve valleys into the landscape by eroding, transporting, and depositing weathered rocks, soil, and landscape by eroding, transporting, and depositing weathered rocks, soil, and sediment.sediment.

A A watershedwatershed or or basinbasin is the area of land bound by a local elevation ridge, referred to as is the area of land bound by a local elevation ridge, referred to as a a drainage dividedrainage divide, where all the water within that area drains downstream from its , where all the water within that area drains downstream from its headwaters to a single outflow location. A watershed can include an entire river system headwaters to a single outflow location. A watershed can include an entire river system from it headwaters to ultimate base level, or smaller watersheds can encompass tributary from it headwaters to ultimate base level, or smaller watersheds can encompass tributary sub-basins that are part of the larger watershed.sub-basins that are part of the larger watershed.

Drainage divides are high elevation ridges that separate one watershed from another.Drainage divides are high elevation ridges that separate one watershed from another.5353

Standards: 5-3Standards: 8-3

Table of Contents

5454

Longitudinal River Longitudinal River ProfileProfile

Ele

vati

on

(fe

et)

0

3,000

Headwaters

UltimateBase level

River Length (Miles)100 0

Steep, high-gradientgentle, low-gradient

This diagram outlines the longitudinal profile of a river basin from the headwaters to the ultimate base level, or sea level. A rivers gradient is steepest near the headwaters and gentlest near the base level. In South Carolina, the steepest sections are often

found in the blue Ridge and Piedmont, while the gentler gradient occurs in the Coastal

Plain. River length, or distance, is measured from the rivers mouth to its headwaters, seemingly reversed from what one might

expect.

Longitudinal Profile and Longitudinal Profile and WatershedsWatershedsHeadwaters:

multiple low-order streams near

drainage divide

Base level: single outflow

andhighest order

stream

1

1

1

2 2

11

3

4

3

4

5

This figure is a hypothetical river basin. The black dotted line represents the drainage divide and the numbers refer to stream order. Any rainfall

that falls within the black dotted line will eventually flow into the main stem river and out at the mouth. Stream order increases from the headwaters to the base level. In this example,

the river is a5th-order river.

Stream Order:Stream Order:1st order and 1st order = 2nd order2nd order and 2nd order = 3rd order3rd order and 3rd order = 4th order4th order and 4th order = 5th orderAnd so on, 5 and 5 =6, 6 and 6 =7th order…

5

Standards: 5-3Standards: 8-3

Table of Contents

South Carolina Rivers and BasinsSouth Carolina Rivers and Basins

5555

Standards: 3-3.5, 3-3.6Standards: 8-3.9

Table of Contents

Dams and LakesDams and Lakes

5656

Dams are control structures on rivers which store and release river water from a lake (reservoir) according to specific operating regimes.

Some dams are run-of-river structures which continually release the same amount of water entering the reservoir, while others are operated as storage facilities for regulated control on water releases.

Although 70 percent of the earth is covered with water, only about 2.5 percent is freshwater, by building dams with reservoirs people are able to store the freshwater and use it as needed.

Dams provide water for drinking, irrigation, hydro-electric power, river navigation, flood control, recreation, and many other needs.

Dams disconnect river channels and can function as local base level controls on stream gradient and store sediment from transporting downstream. They also act as barriers to migrating species, such as fish traveling upstream to spawn, and the controlled water releases alter the downstream ecology of river systems and their floodplains.

Lake Powell and Glen Canyon Dam: Lake Powell and Glen Canyon Dam: Colorado River, ArizonaColorado River, Arizona

Photo: Paul R. Kucher

Lake Murray and Saluda Dam:Lake Murray and Saluda Dam: Saluda River, South Carolina Saluda River, South Carolina

www.sceg.com


Table of Contents

Mountain StreamsMountain Streams Mountain streams are high-gradient, low-order streams sourced from springs, Mountain streams are high-gradient, low-order streams sourced from springs,

rainfall, or snowmelt. They often contain a v-shaped valley, bedrock stream rainfall, or snowmelt. They often contain a v-shaped valley, bedrock stream bottom, rapids, waterfalls, and a very narrow flood plain. bottom, rapids, waterfalls, and a very narrow flood plain.

Mountain streams form the headwaters of larger river basins and they Mountain streams form the headwaters of larger river basins and they generally contain the largest sediment sizes including boulders, cobbles, generally contain the largest sediment sizes including boulders, cobbles, gravel, and coarse sand.gravel, and coarse sand.

Mountain streams often contain localized pools upstream and or downstream Mountain streams often contain localized pools upstream and or downstream of small elevation drops, this pattern is referred to as a step-pool sequence. of small elevation drops, this pattern is referred to as a step-pool sequence. These pools are often important to aquatic ecology and increased biodiversity These pools are often important to aquatic ecology and increased biodiversity in mountain streams. in mountain streams.

5757

Step–pool sequence in the Middle Saluda River, South Carolina

This stream is in the Mountain

Bridge Wilderness Area in South

Carolina. It flows over bedrock and

contains numerous

waterfalls and step-pool

sequences.


Table of Contents

BraidedBraided Braided river patterns occur in high-energy environments that contain an Braided river patterns occur in high-energy environments that contain an

excessive sediment load that is deposited on the bed of the channel. The excessive sediment load that is deposited on the bed of the channel. The stream loses the capacity to transport the sediments and it forces its way stream loses the capacity to transport the sediments and it forces its way through the accumulation of sediments forming an interwoven network of through the accumulation of sediments forming an interwoven network of channels.channels.

The islands between the braided channels are ephemeral and dynamic. The The islands between the braided channels are ephemeral and dynamic. The sediment is continually remobilized, transported and deposited, leaving sediment is continually remobilized, transported and deposited, leaving minimal time for vegetation to establish, as a result they are rarely minimal time for vegetation to establish, as a result they are rarely vegetated. vegetated.

Braided channels tend to be wide and shallow with defined banks that are Braided channels tend to be wide and shallow with defined banks that are higher than the mid-channel islands. higher than the mid-channel islands.

Braided channels occur downstream of areas with high sediment loads. Their Braided channels occur downstream of areas with high sediment loads. Their sediment textures vary from silts, sands, and gravels depending on the sediment textures vary from silts, sands, and gravels depending on the sediment source. sediment source.

5858Copyright © Marli Miller, University of Oregon

This is the braided Resurrection River in

Alaska. The sediment load consists primarily of silt

that has been eroded and weathered from glacial

debris. Braided river patterns may also be

referred to as anastomosing.


Table of Contents

MeanderingMeandering Meandering river patterns are low-gradient, sinuous channels that contain Meandering river patterns are low-gradient, sinuous channels that contain

multiple, individual meander bends that are laterally migrating across the multiple, individual meander bends that are laterally migrating across the flood plain.flood plain.

As they migrate or move across the flood plain they are continuously As they migrate or move across the flood plain they are continuously eroding, transporting, and depositing alluvial sediments. eroding, transporting, and depositing alluvial sediments.

Meandering rivers and their hydrologic conditions create a variety of Meandering rivers and their hydrologic conditions create a variety of depositional and erosional landform features that collectively form the flood depositional and erosional landform features that collectively form the flood plain valley.plain valley.

The primary features of meandering channels are the aggrading pointbar The primary features of meandering channels are the aggrading pointbar deposit on the inside of a meander bend and eroding cut bank along the deposit on the inside of a meander bend and eroding cut bank along the outside of the bend. As the channel migrates laterally across the flood plain, outside of the bend. As the channel migrates laterally across the flood plain, sediments are eroded from the outer cutbank and deposited on the inner sediments are eroded from the outer cutbank and deposited on the inner pointbar. pointbar.

Occasionally, meandering channels cut-off entire meander bends; these cut-Occasionally, meandering channels cut-off entire meander bends; these cut-offs are incorporated into the flood plain as oxbow lakes or in-filled channels. offs are incorporated into the flood plain as oxbow lakes or in-filled channels.

5959

This is an aerial view of the meandering Congaree River and flood plain in Congaree National Park, South Carolina. This image

uses infrared colors instead of true colors; the infrared reflectance

causes healthy vegetation to show up as a reddish-pink color, instead of the green we expect to see. The

bottom right of the image includes a recently cut off meander bend and

oxbow lake.2006 Aerial imagery: http://www.dnr.sc.gov/GIS/gisdata.html


Table of Contents

Entrenched MeandersEntrenched Meanders Entrenched meanders occur when a river channel cuts down into the flood Entrenched meanders occur when a river channel cuts down into the flood

plain or bedrock and the channel is trapped within a single course and it can plain or bedrock and the channel is trapped within a single course and it can not migrate laterally but erodes the landscape by down-cutting. This process not migrate laterally but erodes the landscape by down-cutting. This process will often leave behind numerous terraces of varying width and expose will often leave behind numerous terraces of varying width and expose multiple layers of rock.multiple layers of rock.

The Colorado River flowing through the Grand Canyon in Arizona, provides a The Colorado River flowing through the Grand Canyon in Arizona, provides a classic example of entrenched meanders. Down cutting began as the classic example of entrenched meanders. Down cutting began as the Colorado Plateau was uplifted about 5 million years ago and the river Colorado Plateau was uplifted about 5 million years ago and the river responded by eroding into the valley and has maintained roughly the same responded by eroding into the valley and has maintained roughly the same course ever since. course ever since.

6060Courtesy USGS Photographic Library

Below are the entrenched meanders of the Colorado River and to the right is the first geologic interpretation of the numerous

geologic units exposed by the down cutting river.

Copyright © Michael Collier


Table of Contents

AnabranchingAnabranching Anabranching river patterns contain multiple channels that weave a Anabranching river patterns contain multiple channels that weave a

mosaic through semi-permanent alluvial vegetated islands. The islands are mosaic through semi-permanent alluvial vegetated islands. The islands are often the same height as the flood plain and were likely isolated from the often the same height as the flood plain and were likely isolated from the flood plain by meander bend cutoffs, channel avulsions (abandonment of flood plain by meander bend cutoffs, channel avulsions (abandonment of an entire channel segment), or mid-channel deposition and subsequent an entire channel segment), or mid-channel deposition and subsequent vegetation. vegetation.

Anabranching rivers often occur in alternating combination with other river Anabranching rivers often occur in alternating combination with other river forms, such as meandering, braided, or straight rivers. forms, such as meandering, braided, or straight rivers.

Anabranching rivers provide added habitat complexity and support rich Anabranching rivers provide added habitat complexity and support rich biodiversity. biodiversity.

6161

This section of the Little Pee Dee River in South Carolina represents an

anabranching river, most likely formed by channel avulsion (channel

abandonment) and reoccupation of both the old and new channel. Upstream and downstream from this segment the river is mainly a single meandering channel

with a wide alluvial flood plain and multiple meander bend cutoffs.


Copyright Google, 2008 Table of Contents

StraightStraight

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Table of Contents

Straight river patterns are often the result of reaches that are incised into Straight river patterns are often the result of reaches that are incised into bedrock, follow geological structures, or are engineered by people to not bedrock, follow geological structures, or are engineered by people to not move laterally. move laterally.

They are not as common as meandering or braided streams and straight They are not as common as meandering or braided streams and straight rivers generally only characterize a particular reach of a river channel. rivers generally only characterize a particular reach of a river channel.

Straight reaches in a river system can provide important insight into bedrock Straight reaches in a river system can provide important insight into bedrock controls or abrupt changes in stream gradient. controls or abrupt changes in stream gradient.

This reach of the Lynches River in South Carolina is particularly interesting to geologists and

geomorphologists because the river changes abruptly from a

sinuous, meandering pattern to a very straight channel. The

meandering sections occupy an alluvial flood plain and are able to migrate across the river’s valley. The straight segments are incised into limestone bedrock, and the channel can not move laterally.

Downstream from this large bend the river returns to a meandering

pattern.Data source: www.dnr.sc.gov/gis.html

Meandering reach

Straight reach


Flood plainsFlood plains Flood plains are the landform adjacent Flood plains are the landform adjacent

to the river channel that is influenced to the river channel that is influenced by modern river processes. Flood by modern river processes. Flood plains are constructive, depositional plains are constructive, depositional landforms created by stream flow and landforms created by stream flow and sediment deposition. sediment deposition.

Flood plain environments are Flood plain environments are composed of a mosaic of different composed of a mosaic of different landform features including landform features including cutbankscutbanks, , pointbarspointbars, , natural natural leveeslevees, , crevasse channels crevasse channels and and crevasse splayscrevasse splays, , infilled channels infilled channels and and oxbow lakesoxbow lakes, , backswamps, and , and occasionally yazoo tributaries and occasionally yazoo tributaries and other flood plain channels.other flood plain channels.

6363Copyright ©2008 Google

This aerial view of the Mississippi River Valley contains many typical floodplain features. The darker, green areas are

floodplain forest and they likely flood the most frequently and thus are not

developed with agriculture or housing. The surrounding patchwork represents agricultural fields and other developed

lands that are probably at a higher elevation formed by natural or artificial

levees.

PointbarPointbar

CutbankCutbank

Oxbow Oxbow LakesLakes

Infilled Infilled Channel Channel


Table of Contents

Flood PlainsFlood Plains

6464

Cutbanks Cutbanks form along the outer convex margin of meander bends. Cutbanks , unlike form along the outer convex margin of meander bends. Cutbanks , unlike most floodplain landforms are actually erosional features formed by the lateral most floodplain landforms are actually erosional features formed by the lateral movement of the channel across the flood plain. Flood plain sediments are eroded from movement of the channel across the flood plain. Flood plain sediments are eroded from the cutbank and deposited on pointbar surfaces.the cutbank and deposited on pointbar surfaces.

Pointbars Pointbars are concave, depositional landforms that form opposite of the eroding are concave, depositional landforms that form opposite of the eroding cutbanks, and they develop in concert with the laterally migrating river channel. cutbanks, and they develop in concert with the laterally migrating river channel. Pointbars are typically composed of sands, gravel, silts, and clay deposits, that form Pointbars are typically composed of sands, gravel, silts, and clay deposits, that form arcuate, arcuate, meander-scroll ridgesmeander-scroll ridges. .

Natural levees Natural levees are depositional landforms formed from the vertical accumulation of are depositional landforms formed from the vertical accumulation of sediments deposited during flood events. Natural levees form topographically higher sediments deposited during flood events. Natural levees form topographically higher surfaces adjacent to the river channel, that generally consist of stratified, well-sorted surfaces adjacent to the river channel, that generally consist of stratified, well-sorted sands, silts, and clays. Natural levees deposits are thickest and coarsest close to the sands, silts, and clays. Natural levees deposits are thickest and coarsest close to the channel and they become progressively thinner, and finer with increasing distance from channel and they become progressively thinner, and finer with increasing distance from the channel. the channel.

Crevasse channels and splaysCrevasse channels and splays are breaches in the natural levee that result in the fan-are breaches in the natural levee that result in the fan-shaped deposition of flood deposits, beyond or over levee deposits. Crevasse channels shaped deposition of flood deposits, beyond or over levee deposits. Crevasse channels can produce flooding in backswamp areas, even before the levees are submerged by can produce flooding in backswamp areas, even before the levees are submerged by floodwaters. floodwaters.

Oxbow lakes Oxbow lakes or or infilled channels infilled channels form when a meander bend is cut off from the main form when a meander bend is cut off from the main river and abandoned in the floodplain. Abandoned meanders can occur in various stages river and abandoned in the floodplain. Abandoned meanders can occur in various stages from flooded oxbow lakes to being completely infilled with sediment deposits. from flooded oxbow lakes to being completely infilled with sediment deposits.

Backswamps Backswamps are typically low-lying areas of the floodplain beyond the natural levee are typically low-lying areas of the floodplain beyond the natural levee deposits. Backswamps contain the finest-textured flood plain deposits and may even deposits. Backswamps contain the finest-textured flood plain deposits and may even develop organic-rich soils from the forest litter. They often form along the margins or develop organic-rich soils from the forest litter. They often form along the margins or edge of the floodplain, and are usually influenced by connections to the groundwater. edge of the floodplain, and are usually influenced by connections to the groundwater.

Yazoo tributaries Yazoo tributaries are stream networks that enter the floodplain but the natural levee are stream networks that enter the floodplain but the natural levee prevents the stream from flowing into the river. As a result the yazoo tributary flows prevents the stream from flowing into the river. As a result the yazoo tributary flows parallel to the mainstem river before reaching a breach in the levee or occupying the parallel to the mainstem river before reaching a breach in the levee or occupying the course of an abandoned meander that allows the stream to cross the levee deposits and course of an abandoned meander that allows the stream to cross the levee deposits and flow into the river. flow into the river.


Table of Contents

Flood PlainsFlood Plains

6565

Both of these images are GIS-based models from Both of these images are GIS-based models from the Congaree River floodplain in Congaree National the Congaree River floodplain in Congaree National

Park. The image on the left is a clip from a flood Park. The image on the left is a clip from a flood model that shows the depth of flooding during a model that shows the depth of flooding during a

large flood event. The natural levee adjacent to the large flood event. The natural levee adjacent to the channel is one of the topographically highest channel is one of the topographically highest

features and it floods the least. The abandoned features and it floods the least. The abandoned meanders and back swamps are topographically meanders and back swamps are topographically lower and flood more frequently and to greater lower and flood more frequently and to greater depths. The channel networks fill up with water depths. The channel networks fill up with water

connecting the oxbow lakes to the main stem river. connecting the oxbow lakes to the main stem river. The image below is from a high resolution digital The image below is from a high resolution digital elevation model (DEM) of a floodplain. The DEM is elevation model (DEM) of a floodplain. The DEM is useful for mapping the different landform features useful for mapping the different landform features

on a floodplain.on a floodplain.

Oxbow Oxbow lakelake

Infilled Infilled ChannelChannel

Natural Levee

Natural Levee

Crevasse Crevasse ChannelsChannels

Meander-Scroll Meander-Scroll ridgesridges


Table of Contents

River TerracesRiver Terraces River terraces are older remnant flood plain surfaces that are higher in River terraces are older remnant flood plain surfaces that are higher in

elevation than the modern flood plain. They may occur on one or both sides elevation than the modern flood plain. They may occur on one or both sides of the valley.of the valley.

Terraces are formed when the river channel cuts down into the flood plain Terraces are formed when the river channel cuts down into the flood plain and laterally erodes the alluvial valley, carving a new river channel and flood and laterally erodes the alluvial valley, carving a new river channel and flood plain entrenched within the older flood plain surfaces. Down cutting can plain entrenched within the older flood plain surfaces. Down cutting can occur because of hydrologic or sedimentary changes in the headwaters or occur because of hydrologic or sedimentary changes in the headwaters or valley gradient changes caused by a retreating sea-level and lowered or valley gradient changes caused by a retreating sea-level and lowered or extended base-level. Terraces can also form from tectonics and valley extended base-level. Terraces can also form from tectonics and valley uplifting.uplifting.

Terraces are generally isolated from the more recent river processes and Terraces are generally isolated from the more recent river processes and may only flood during 100 or 500 year flood events. River terraces are often may only flood during 100 or 500 year flood events. River terraces are often archeological hot spots because they contain artifacts from historic colonies archeological hot spots because they contain artifacts from historic colonies that used the river and flood plain.that used the river and flood plain.

6666

This river has gone through This river has gone through several different episodes of several different episodes of

down cutting and rejuvenation. down cutting and rejuvenation. The modern flood plain is The modern flood plain is preceded by four different preceded by four different

terraces that all reflect distinct terraces that all reflect distinct periods of environmental periods of environmental

conditions or valley gradients, conditions or valley gradients, each different from the other. each different from the other.

Over time, it is possible that the Over time, it is possible that the river will down-cut again river will down-cut again

abandoning a fifth terrace. abandoning a fifth terrace.

Copyright©Louis Maher, University of Wisconsin

Terrace 1Terrace 1

Terrace 2Terrace 2

Terrace 3Terrace 3

River Channel and Modern Flood River Channel and Modern Flood PlainPlain

Terrace 4Terrace 4


Table of Contents

WaterfallsWaterfalls Waterfalls occur where there is resistant bedrock, abrupt changes in bedrock Waterfalls occur where there is resistant bedrock, abrupt changes in bedrock

resistance, or along fractures or faults in the bedrock. resistance, or along fractures or faults in the bedrock. Less resistant materials are weathered more quickly than resistant rocks, creating Less resistant materials are weathered more quickly than resistant rocks, creating

stair-stepped ledges or drop offs where waterfalls occur. Less resistant rocks may stair-stepped ledges or drop offs where waterfalls occur. Less resistant rocks may also form pools between resistant rocks that form waterfalls. also form pools between resistant rocks that form waterfalls.

Faults and fractures often provide natural pathways for the downslope movement of Faults and fractures often provide natural pathways for the downslope movement of water. water.

The location of the waterfalls origin may be referred to as a “knick-point”, continued The location of the waterfalls origin may be referred to as a “knick-point”, continued weathering by the stream flow causes the knick-point to slowly migrate upstream. weathering by the stream flow causes the knick-point to slowly migrate upstream.

Most waterfalls in South Carolina occur along streams in the Blue Ridge, Piedmont, Most waterfalls in South Carolina occur along streams in the Blue Ridge, Piedmont, and the along the Regional Fall Line where there are rock layers of varying and the along the Regional Fall Line where there are rock layers of varying resistance.resistance.

6767Copyright Copyright © Marli Miller, University of Oregon© Marli Miller, University of Oregon

This waterfall was formed by differential This waterfall was formed by differential weathering between the softer shale and weathering between the softer shale and

harder more resistant limestone. harder more resistant limestone.

Photo: SCGS

Lower White Water Lower White Water Falls in the Jocassee Falls in the Jocassee

Gorges area of Gorges area of South Carolina South Carolina

drops nearly 200 ft. drops nearly 200 ft. Here, the Toxaway Here, the Toxaway

Gneiss forms a Gneiss forms a resistant bedrock resistant bedrock

that the Lower that the Lower White Water River White Water River flows over before flows over before draining into Lake draining into Lake

Jocasse. Jocasse.


Table of Contents

Alluvial FansAlluvial Fans Alluvial fans are fan-shaped fluvial deposits that accumulate at the Alluvial fans are fan-shaped fluvial deposits that accumulate at the

base of stream where it flows out from a steep gradient and base of stream where it flows out from a steep gradient and enters into a lower-gradient flood plain or valley setting.enters into a lower-gradient flood plain or valley setting.

The stream enters the valley carrying a higher capacity sediment The stream enters the valley carrying a higher capacity sediment load than it can continue to carry, and as a result it deposits the load than it can continue to carry, and as a result it deposits the sediments as an alluvial fan.sediments as an alluvial fan.

Alluvial fans generally form in arid environments with a high Alluvial fans generally form in arid environments with a high sediment load and where there is minimal vegetation to disrupt sediment load and where there is minimal vegetation to disrupt the fan formation. the fan formation.

Alluvial fans may form from a single high-flow event or from the Alluvial fans may form from a single high-flow event or from the accumulation of multiple events. accumulation of multiple events.

6868Copyright © Marli Miller, University of Oregon

This alluvial fan is carrying a high This alluvial fan is carrying a high sediment load from material weathered sediment load from material weathered from the mountains. The dark line along from the mountains. The dark line along

the edge of the fan is a road. Because the the edge of the fan is a road. Because the road is not buried by recent deposits it road is not buried by recent deposits it suggest that this fan is not currently as suggest that this fan is not currently as

active as it was in the past.active as it was in the past.


Table of Contents

GullysGullys Gullys are formed by hillslope erosion. Gullys are formed by hillslope erosion. Rainwater runoff draining over the surface of a hillslope generates Rainwater runoff draining over the surface of a hillslope generates

erosive overland flows that remove weathered rocks and soil. erosive overland flows that remove weathered rocks and soil. When multiple gullys form they produce a disconnected network When multiple gullys form they produce a disconnected network

of headwater channels that dissect the hillslope and increase soil of headwater channels that dissect the hillslope and increase soil erosion.erosion.

Gullys primarily form on disturbed hillslopes where forest and Gullys primarily form on disturbed hillslopes where forest and vegetation have been cleared. vegetation have been cleared.

6969

The forest was cleared from this hill The forest was cleared from this hill slope and corn was planted on the slope and corn was planted on the bare soil. Following the first few bare soil. Following the first few

rain events, gullys began to form as rain events, gullys began to form as a result of soil erosion. The gullys a result of soil erosion. The gullys

only carry water during rainfall only carry water during rainfall events. events.


Table of Contents

Karst LandformsKarst Landforms

CavernsCaverns SinkholesSinkholes Disappearing StreamsDisappearing Streams SpringsSprings TowersTowers

7070

Karst is a term used to describe landscapes that are formed by chemical weathering process controlled by groundwater activity. Karst landscapes are predominantly composed of limestone rock that contains > 70 percent calcium carbonate.

Onondaga Cave in Missouri is a karst Onondaga Cave in Missouri is a karst landform formed by chemical landform formed by chemical

solution in carbonate limestone solution in carbonate limestone rocks. Features within Onondaga rocks. Features within Onondaga

Cave include stalagmites, stalactites, Cave include stalagmites, stalactites, dripstones and active flowstone dripstones and active flowstone

deposits. Missouri contains so many deposits. Missouri contains so many caves that it is nicknamed the “Cave caves that it is nicknamed the “Cave

State”. State”.

Copyright© Oklahoma University


Table of Contents

CavernsCaverns Limestone caverns and caves are large sub-Limestone caverns and caves are large sub-

surface voids where the rocks has been surface voids where the rocks has been dissolved by carbonation. dissolved by carbonation.

Caverns and their various features form below Caverns and their various features form below the ground water table where dissolved the ground water table where dissolved minerals drip through the ceiling of the cave minerals drip through the ceiling of the cave through fractures and joints in the limestone. through fractures and joints in the limestone. Over time this mineral-rich ground water Over time this mineral-rich ground water dissolves the rocks until eventually entire dissolves the rocks until eventually entire caverns are formed. caverns are formed.

Calcium carbonate precipitates out of the Calcium carbonate precipitates out of the saturated carbonate solution and accumulates saturated carbonate solution and accumulates as deposits. as deposits. StalactitesStalactites are deposits that grow are deposits that grow from the ceiling downward and from the ceiling downward and stalagmitesstalagmites are deposits that grow from the ground up. If are deposits that grow from the ground up. If the stalactite and stalagmites join they form a the stalactite and stalagmites join they form a continuous column.continuous column.

Mammoth Cave in Kentucky and Carlsbad Mammoth Cave in Kentucky and Carlsbad Caverns in New Mexico are two of the largest Caverns in New Mexico are two of the largest cave systems in North America and the world. cave systems in North America and the world.

Not all caves are formed by karst processes. Not all caves are formed by karst processes. Some caves are formed by lava tubes and Some caves are formed by lava tubes and others are formed by the erosion forces of large others are formed by the erosion forces of large amounts of ground water flow. amounts of ground water flow.

7171

This image of the “Chinese This image of the “Chinese Theatre” in Carlsbad Caverns Theatre” in Carlsbad Caverns National Park illustrates how National Park illustrates how

stalactites and stalagmites can stalactites and stalagmites can join to form columns. Notice the join to form columns. Notice the

person in the lower left for person in the lower left for scale!scale!


Table of Contents

SinkholesSinkholes Sinkholes are collapsed limestone features that develop in karst Sinkholes are collapsed limestone features that develop in karst

landscapes. Sinkholes form when the limestone bedrock is chemically landscapes. Sinkholes form when the limestone bedrock is chemically weathered by naturally occurring chemicals in the ground water. The weathered by naturally occurring chemicals in the ground water. The ground water slowly dissolves the limestone rock below the surface until it ground water slowly dissolves the limestone rock below the surface until it eventually becomes unstable and collapses creating local depressional eventually becomes unstable and collapses creating local depressional features. Sinkholes occur in a range of sizes, and can be temporarily, features. Sinkholes occur in a range of sizes, and can be temporarily, seasonally, or permanently filled with water. seasonally, or permanently filled with water.

Sinkholes pose a threat to developed areas, because if they occur beneath Sinkholes pose a threat to developed areas, because if they occur beneath houses or other infrastructure they may collapse with the sinkhole.houses or other infrastructure they may collapse with the sinkhole.

Increased pressure on water resources and depleted ground water tables Increased pressure on water resources and depleted ground water tables can trigger sinkholes to collapse under the pressure of gravity or the void can trigger sinkholes to collapse under the pressure of gravity or the void formed by the depleted ground water. formed by the depleted ground water.

7272Photo: USGS

The left is an aerial view of the Tres Pueblos sinkhole The left is an aerial view of the Tres Pueblos sinkhole in Puerto Rico. Solution of the underlying rock in Puerto Rico. Solution of the underlying rock

caused bedrock, soil, and vegetation to collapse into caused bedrock, soil, and vegetation to collapse into the sinkhole feature. The images above are from the sinkhole feature. The images above are from urban areas in Florida where sinkholes damaged urban areas in Florida where sinkholes damaged

several homes and businesses.several homes and businesses.

www.sfwmd.state.fl.us


Table of Contents

Disappearing StreamsDisappearing Streams Disappearing streams are streams that flow on the surface and then Disappearing streams are streams that flow on the surface and then

seemingly “disappear” below ground. Disappearing streams disappear into a seemingly “disappear” below ground. Disappearing streams disappear into a sinkhole or other karst solution features such as caves. They may also sinkhole or other karst solution features such as caves. They may also disappear into factures or faults in the bedrock near the stream. disappear into factures or faults in the bedrock near the stream. Disappearing streams are also referred to as losing streams, sinks, or sieves. Disappearing streams are also referred to as losing streams, sinks, or sieves.

Disappearing streams will often continue flowing underground and may Disappearing streams will often continue flowing underground and may resurface at another location downstream from where they disappeared. resurface at another location downstream from where they disappeared.

Disappearing streams often maintain a connection with the local or regional Disappearing streams often maintain a connection with the local or regional ground water, and thus it is important to protect their drainage basin from ground water, and thus it is important to protect their drainage basin from polluted run-off to prevent ground water contamination from harmful polluted run-off to prevent ground water contamination from harmful pollutants or chemicals. pollutants or chemicals.

7373

The stream in this image on the left The stream in this image on the left disappears into the limestone and disappears into the limestone and

continues to flow underground before continues to flow underground before resurfacing downstream. resurfacing downstream. www.northeastiowarcd.org

Disappearing

Stream


Table of Contents

SpringsSprings Karst springs are locations where groundwater emerges from the limestone Karst springs are locations where groundwater emerges from the limestone

and flows across the surface forming a stream or contained pool. and flows across the surface forming a stream or contained pool. The flow of Karst springs is generally dependant on the weather and The flow of Karst springs is generally dependant on the weather and

climate. Some are more permanent than others, while others only flow climate. Some are more permanent than others, while others only flow following rainfall or snowmelt events. Springs that are connected to following rainfall or snowmelt events. Springs that are connected to aquifers flow year-round and support rich aquatic biodiversity.aquifers flow year-round and support rich aquatic biodiversity.

Karst springs generally do not support good water quality, and thus are not Karst springs generally do not support good water quality, and thus are not safe for drinking without filtering the water first; however, the springs often safe for drinking without filtering the water first; however, the springs often provide fun recreational opportunities and can be a popular place for provide fun recreational opportunities and can be a popular place for swimming and snorkeling.swimming and snorkeling.

7474http://www.floridasprings.com/about.html

Karst springs provide cool, clear, water that Karst springs provide cool, clear, water that is inviting for people to swim and snorkel is inviting for people to swim and snorkel

in. The left is from a karst spring in Florida in. The left is from a karst spring in Florida an the image above is from Barton Springs, an the image above is from Barton Springs,

a karst spring in the Texas Hill Country.a karst spring in the Texas Hill Country.


Table of Contents

TowersTowers Karst towers create a unique topography where the landscape is mottled Karst towers create a unique topography where the landscape is mottled

with a maze of steep, isolated limestone hills.with a maze of steep, isolated limestone hills. The towers are weathered features formed where the limestone beds are The towers are weathered features formed where the limestone beds are

thick and highly jointed, as a result the remnant towers contain caves and thick and highly jointed, as a result the remnant towers contain caves and a variety of other passageways for water to percolate along fractures in a variety of other passageways for water to percolate along fractures in the joints. the joints.

Karst towers occur in tropical climates of Puerto Rico, western Cuba, Karst towers occur in tropical climates of Puerto Rico, western Cuba, southern China, and northern Vietnam. Lush vegetation from the tropical southern China, and northern Vietnam. Lush vegetation from the tropical climates produce greater carbon dioxide that concentrates as a carbonic climates produce greater carbon dioxide that concentrates as a carbonic acid in the rain water which facilitates the weathering processes which acid in the rain water which facilitates the weathering processes which form karst towers.form karst towers.

7575

These karst towers in These karst towers in southern China produce an southern China produce an

interesting and unique interesting and unique landscape. Although they landscape. Although they have a very thin soil, the have a very thin soil, the

towers are capable of towers are capable of supporting lush tropical supporting lush tropical

vegetation. vegetation.

Photo: Pat Kambesis


Table of Contents

Aeolian LandformsAeolian Landforms

DunesDunes Loess FormationsLoess Formations Carolina BaysCarolina Bays

7676

Aeolian landforms are formed by the deposition of windblown sediments. The sediments are generally sourced from deserts, glacial deposits, rivers, or coastal shorelines. Aeolian sediments are often composed of well-rounded, sand-to silt-sized particles, that are weathered by wind abrasion during transport. Sediments are deposited when the velocity of the wind falls and there is not enough energy available to entrain and transport the sediments. Sands will begin to accumulate wherever they are deposited and often continue to move along the ground.

Photo courtesy of SCDNRPhoto courtesy of SCDNR

Coastal parabolic sand dunes in Coastal parabolic sand dunes in The ACE Basin region of South The ACE Basin region of South

Carolina.Carolina.


Table of Contents

DunesDunes Dunes are formed as mounds or ridges of aeolian sand deposits and are then sculpted by Dunes are formed as mounds or ridges of aeolian sand deposits and are then sculpted by

near- surface wind processes, such as near- surface wind processes, such as saltationsaltation. Saltation transports sediment up slope . Saltation transports sediment up slope on the windward side and once the sediments reach the crest they fall over and on the windward side and once the sediments reach the crest they fall over and accumulate as a steeper slope on the leeward side of the dune, referred to as the accumulate as a steeper slope on the leeward side of the dune, referred to as the slip slip faceface. This section will cover . This section will cover barchanbarchan, , transversetransverse, , longitudinallongitudinal,, parabolicparabolic, and , and star star dunesdunes. An area covered by many dunes is an . An area covered by many dunes is an ergerg..

Barchan dunes Barchan dunes are solitary, crescent shaped dunes with their tips pointing downwind. are solitary, crescent shaped dunes with their tips pointing downwind. They form where sand source is limited, wind direction is constant, and the ground is void They form where sand source is limited, wind direction is constant, and the ground is void of vegetation. They can reach heights of 30 meters and spread nearly 300 meters. of vegetation. They can reach heights of 30 meters and spread nearly 300 meters.

Transverse dunes Transverse dunes are a series of long ridges that are parallel to one another, and are are a series of long ridges that are parallel to one another, and are perpendicular to the prevailing wind. They form in areas where the prevailing winds are perpendicular to the prevailing wind. They form in areas where the prevailing winds are steady, there is an abundant supply of sand, and vegetation is sparse. They can reach steady, there is an abundant supply of sand, and vegetation is sparse. They can reach heights of 200 meters and may extend for 100’s of kilometers.heights of 200 meters and may extend for 100’s of kilometers.

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Barchan Dunes

http://www.nps.gov/archive/grsa/resources/images/lgformat/barchan.jpg

John McCauley, USGS

WindWind

Transverse Dunes

John McCauley, USGS

WindWindWind directionWind direction

slip slip faceface

Sand Sand avalancheavalanche

Dune Dune movementmovement


Table of Contents

http://www.nps.gov/archive/grsa/

DunesDunes

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Longitudinal dunes, Longitudinal dunes, also referred to as also referred to as Seifs Seifs are long ridges of sand that form are long ridges of sand that form parallel to the prevailing wind. They form in areas where there is moderate supply of parallel to the prevailing wind. They form in areas where there is moderate supply of sand, and they range in size 5-10 meters tall to 100 meters in height and width.sand, and they range in size 5-10 meters tall to 100 meters in height and width.

Star dunes Star dunes are complex dunes with a central mound surrounded by radiating points. From above they resemble a star shape. They are formed by shifting wind patterns that create the unique star shape. Star dunes can reach heights of 90 meters and extend outward for over twice their height.

Parabolic dunes Parabolic dunes are similar in form to barchan dunes except their tips point into the wind. They form as blow outs where the sand has carved out the sediments and deposited it onto the leeward side. Parabolic dunes form inland from coastal shorelines from sands on the beach.Star Dune in Namib Desert, Namibia

http://en.wikipedia.org/wiki/Image:Dune_7_in_the_Namib_Desert.jpeg

Win

dW

ind

Photo: www.googleearth.com Eve, Montana

Longitudinal Dune


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http://www.googleearth.com/

LoessLoess Loess deposits are regionally extensive accumulations of Loess deposits are regionally extensive accumulations of

windblown silt resulting from thousands of dust storms.windblown silt resulting from thousands of dust storms. During the dust storms, silt is entrained, transported, and During the dust storms, silt is entrained, transported, and

deposited as loess. Loess deposits are generally sourced deposited as loess. Loess deposits are generally sourced from either glacial or desert terranes, and silt may be from either glacial or desert terranes, and silt may be transported for 100's of miles before being deposited. transported for 100's of miles before being deposited.

Loess deposits are generally coarsest and thickest close Loess deposits are generally coarsest and thickest close to their source, and they decrease in thickness and grain to their source, and they decrease in thickness and grain size with increasing distance from their source.size with increasing distance from their source.

Loess is not stratified, meaning it lacks distinctive layers. Loess is not stratified, meaning it lacks distinctive layers. Instead they are massive accumulations of silt. Loess Instead they are massive accumulations of silt. Loess deposits range from 30 to >100 meters thick, and they deposits range from 30 to >100 meters thick, and they provide very fertile soils for agriculture and farmland. provide very fertile soils for agriculture and farmland.

The most extensive loess deposit occurs in western and The most extensive loess deposit occurs in western and northern China, and it contains sediments that were northern China, and it contains sediments that were blown from the deserts of Central Asia.blown from the deserts of Central Asia.

In the United States, extensive loess deposits occur in In the United States, extensive loess deposits occur in South Dakota, North Dakota, Nebraska, Iowa, Missouri, South Dakota, North Dakota, Nebraska, Iowa, Missouri, Mississippi, and Illinois. These deposits were sourced Mississippi, and Illinois. These deposits were sourced from glacial sediments.from glacial sediments.

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This loess and sandstone contact is from a quarry near Vicksburg, Mississippi where

both deposits are being mined. This loess was sourced

from glacial till and blown down the Mississippi River Valley. The person in the

picture provides a context for the thickness of the loess

deposit.

Photo: SCGS

LoessLoess

SandstoneSandstone


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YardangYardang A yardang is an elongate ridge or remnant rock feature sculpted by abrasive wind A yardang is an elongate ridge or remnant rock feature sculpted by abrasive wind

erosion.erosion. Yardangs occur in arid environments where prevailing winds come from a single Yardangs occur in arid environments where prevailing winds come from a single

direction. The winds must be strong, steady, and carry a coarse-sediment load that direction. The winds must be strong, steady, and carry a coarse-sediment load that weathers the exposed face of the yardang.weathers the exposed face of the yardang.

Yardangs are sculpted into a variety of forms, and some may resemble common Yardangs are sculpted into a variety of forms, and some may resemble common objects or human-like forms. objects or human-like forms.

Mega-yardangs are those that are several kilometers wide and hundreds of meters Mega-yardangs are those that are several kilometers wide and hundreds of meters high, meso-yardangs are only a few meters high and 10-15 meters long, and micro-high, meso-yardangs are only a few meters high and 10-15 meters long, and micro-yardangs may only be a few centimeters in size.yardangs may only be a few centimeters in size.

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Yardangs are eroded over long time periods and

occur in a variety of sizes and forms. The Egyptians

would often sculpt yardangs into animal and

human forms. Some ancient cultures also

carved caves into yardangs and used them for dwellings or sacred

religious places.


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Riverine Dunes and Sand SheetsRiverine Dunes and Sand Sheets Riverine sand dunes occur on flood plains throughout the South Eastern United Riverine sand dunes occur on flood plains throughout the South Eastern United

States Coastal Plain. They sit 10-30 feet above the flood plain and are composed of States Coastal Plain. They sit 10-30 feet above the flood plain and are composed of thick uniform deposits of well-sorted fine to coarse sands. thick uniform deposits of well-sorted fine to coarse sands.

Most dunes are oriented from the northwest to southeast, and in many cases they Most dunes are oriented from the northwest to southeast, and in many cases they parallel river channels. From their orientation and shape, it is suggested that most parallel river channels. From their orientation and shape, it is suggested that most are transverse dunes. are transverse dunes.

Recent-dating indicate that dunes formed during the late Quaternary, with most dune Recent-dating indicate that dunes formed during the late Quaternary, with most dune ages ranging from 15,000-100,000 years old. ages ranging from 15,000-100,000 years old.

Riverine sand sheets are depositional eolian landforms that occur in association with Riverine sand sheets are depositional eolian landforms that occur in association with riverine sand dunes. They extend leeward (downwind or away from the wind) from riverine sand dunes. They extend leeward (downwind or away from the wind) from the dune and become progressively thinner with increasing distance away from the the dune and become progressively thinner with increasing distance away from the dune. The sand sheets are composed of the same homogenous sands that form the dune. The sand sheets are composed of the same homogenous sands that form the dunes.dunes.

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This digital elevation model (DEM) of the confluence area between the Wateree

and Congaree Rivers, in the Coastal Plain of South Carolina contains a riverine sand

dune. The sand dune is about ten feet higher than the surrounding flood plain and rarely floods except during 100-500 year flood events. For this reason, it is hypothesized that early explorers and

Native American Indians may have lived on this sand dune and farmed in the

surrounding flood plain.

Riverine Dune Elevation ~90 Riverine Dune Elevation ~90 ftftSurrounding Flood plain ~ Surrounding Flood plain ~ 80 ft 80 ft

Wate

ree R

iver

Congaree River


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Carolina BaysCarolina Bays Carolina Bays areCarolina Bays are oval or elliptical, depressional wetland features enclosed by a low oval or elliptical, depressional wetland features enclosed by a low

sandy ridge. The depth of Carolina Bays varies depending on their size and land use sandy ridge. The depth of Carolina Bays varies depending on their size and land use history, most average about 5-15 feet deep; however, some have been measured with history, most average about 5-15 feet deep; however, some have been measured with depths greater than 30 feet . Sand rims enclosing the Carolina Bays also vary in size, depths greater than 30 feet . Sand rims enclosing the Carolina Bays also vary in size, but generally range from 5-15 feet.but generally range from 5-15 feet.

The origin of Carolina Bays is currently debatable. Most Geologists agree that they are The origin of Carolina Bays is currently debatable. Most Geologists agree that they are eolian landforms. Carolina Bays were formed 100,000-30,000 years ago, during the eolian landforms. Carolina Bays were formed 100,000-30,000 years ago, during the Quaternary and occur through the coastal plain of Georgia, South Carolina, North Quaternary and occur through the coastal plain of Georgia, South Carolina, North Carolina, Virginia, and Maryland.Carolina, Virginia, and Maryland.

Carolina Bays occur in varying stages of flooding dependant on their land-use history, Carolina Bays occur in varying stages of flooding dependant on their land-use history, rainfall, and connection to ground water. Carolina Bays can be dry, temporarily rainfall, and connection to ground water. Carolina Bays can be dry, temporarily flooded, or support a permanent lake.flooded, or support a permanent lake.

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Most Carolina Bays have their longest axis oriented from northwest to

southeast, although there are a few oriented in other directions. The sand

rims are largest along the southeastern edge, but in some cases may be

completely lacking. Many Carolina Bays have been drained to support agriculture. Undisturbed Carolina Bays contain unique

assemblages of wetland plants and aquatic organisms. This aerial image contains four Carolina Bays, three of which support agriculture and one, Woods Bay, that is protected by the

Department of Natural Resources Heritage Trust Program.

11

22

33

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ww.maps.google.com


Table of Contents

Coastal LandformsCoastal Landforms

Littoral ZoneLittoral Zone BeachesBeaches Barrier IslandsBarrier Islands Beach RidgesBeach Ridges SpitsSpits DeltasDeltas Coastal CliffsCoastal Cliffs Marine TerracesMarine Terraces Wave-Cut ScarpsWave-Cut Scarps

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Hawaiian coastline

Photo source: SCGS

Coastal landforms include a diverse array of shoreline and near-shoreline features, as well as some coastal plain landforms far removed from the modern ocean by long term sea-level changes. This section will explore both constructive and destructive landforms formed by current coastal processes, as well as marine related landforms that were formed during periods of higher sea level.

Standards: 3-3.5, 3-3.6, 3-3.8Standards: 5-3.1, 5-3.4Standards: 8-3.7, 8-3.9

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Littoral ZoneLittoral Zone The littoral zone extends inland to the highest water line during storms and The littoral zone extends inland to the highest water line during storms and

seaward to the furthest area where shoreline wave processes stop influencing seaward to the furthest area where shoreline wave processes stop influencing sediment transport and deposition on the seafloor and includes several coastal sediment transport and deposition on the seafloor and includes several coastal landforms. landforms.

The shoreline refers to the exact area where the land meets the sea, and coast The shoreline refers to the exact area where the land meets the sea, and coast refers to the land adjacent to the shoreline. The ‘coastal area’, includes the refers to the land adjacent to the shoreline. The ‘coastal area’, includes the coast, shoreline, and near-shore area. coast, shoreline, and near-shore area.

The littoral zone is a continuously changing environment, and it can shift The littoral zone is a continuously changing environment, and it can shift inland or seaward depending on changes in sea level. Rising sea-level will inland or seaward depending on changes in sea level. Rising sea-level will submerge the coastal areas, and a drop in sea level will produce coastline submerge the coastal areas, and a drop in sea level will produce coastline emergence.emergence.

Sea level is commonly referred to and measured as mean sea level (MSL). Sea level is commonly referred to and measured as mean sea level (MSL). Mean sea level is a value based on the average tidal levels recorded hourly for Mean sea level is a value based on the average tidal levels recorded hourly for a given site over at least a 19-year record. Present MSL measurements a given site over at least a 19-year record. Present MSL measurements indicate that sea level is currently rising.indicate that sea level is currently rising.

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Littoral Zone

Image courtesy of US Navy


Table of Contents

BeachesBeaches Beaches are depositional landforms along the coastal area where sediment is Beaches are depositional landforms along the coastal area where sediment is

transported and deposited by waves and currents. Although the sediment transported and deposited by waves and currents. Although the sediment along the beach is continually being mobilized there is an overall net accretion along the beach is continually being mobilized there is an overall net accretion of deposition.of deposition.

The width of the beaches vary from one location to another and from one The width of the beaches vary from one location to another and from one shoreline to another. In some locations a shoreline might even lack a beach shoreline to another. In some locations a shoreline might even lack a beach altogether. altogether.

Most beaches are dominated by sand-sized quartz grains, and shells or shell Most beaches are dominated by sand-sized quartz grains, and shells or shell fragments. However, this can be highly variable depending on the landscape fragments. However, this can be highly variable depending on the landscape that drains into the ocean and near-shore sediment sources. For example, that drains into the ocean and near-shore sediment sources. For example, some beaches in the Hawaiian islands consist of coarse, red and black rock some beaches in the Hawaiian islands consist of coarse, red and black rock fragments formed by weathered lava; and in France and Italy many beaches fragments formed by weathered lava; and in France and Italy many beaches consist of pebbles and cobbles.consist of pebbles and cobbles.

Sediment movement along the beach is referred to as beach drift, and it Sediment movement along the beach is referred to as beach drift, and it generally follows long shore currents traveling along a directional trend generally follows long shore currents traveling along a directional trend produced as waves approach the shallower water in the surf zone near the produced as waves approach the shallower water in the surf zone near the shoreline. shoreline.

8585Photo: SCGS

Beaches often stabilize shorelines by absorbing or deflecting wave and current

energy. During large storms, such as hurricanes, beaches can experience

extensive erosion, and it can be years before they are replenished. Beaches

provide numerous recreational activities and are a popular destination for

vacationers.


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Barrier IslandsBarrier Islands Barrier islands, also referred to as barrier beaches, are long, narrow, Barrier islands, also referred to as barrier beaches, are long, narrow,

depositional landforms, that form parallel to the coastline and may or may not depositional landforms, that form parallel to the coastline and may or may not connect to the mainland. They are the first line of protection against hurricane connect to the mainland. They are the first line of protection against hurricane storm surge.storm surge.

They are generally composed of quartz sands, and they form along coasts They are generally composed of quartz sands, and they form along coasts where there is a substantial supply of sand entering the ocean from Coastal where there is a substantial supply of sand entering the ocean from Coastal Plain rivers. Plain rivers.

Barrier islands often form where tidal process are minimal.Barrier islands often form where tidal process are minimal. The landward side of the barrier islands may contain tidal flats, marshes, The landward side of the barrier islands may contain tidal flats, marshes,

swamps, lagoons, coastal dunes, and beaches. swamps, lagoons, coastal dunes, and beaches. Similar to beaches, barrier islands form in relation to, long-shore current Similar to beaches, barrier islands form in relation to, long-shore current

processes and overtime adjust to sea-level changes.processes and overtime adjust to sea-level changes. Classic examples of barrier islands include North Carolina’s Outer Banks and Classic examples of barrier islands include North Carolina’s Outer Banks and

Texas’s Padre Island. Both of these barrier islands have National Park Service Texas’s Padre Island. Both of these barrier islands have National Park Service lands that preserve natural coastal processes and protect plant and wildlife lands that preserve natural coastal processes and protect plant and wildlife habitat from human impacts.habitat from human impacts.

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Image: NOAA


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Beach RidgesBeach Ridges Beach ridges are wave-deposited ridges that form parallel to the coastline. Beach ridges are wave-deposited ridges that form parallel to the coastline.

They are composed of gravel, sands, and shell fragments, and in some They are composed of gravel, sands, and shell fragments, and in some cases they may be capped by aeolian sands blown from the beach.cases they may be capped by aeolian sands blown from the beach.

If sea-level retreat or regional uplifting occurs after the deposition of a If sea-level retreat or regional uplifting occurs after the deposition of a beach ridge it is incorporated into the mainland as a raised elevation ridge beach ridge it is incorporated into the mainland as a raised elevation ridge near the coast. Beach ridges may be deposited one after another or they near the coast. Beach ridges may be deposited one after another or they may be separated by swale like features that form marshes, swamps, and may be separated by swale like features that form marshes, swamps, and other low-lying wetland environments. other low-lying wetland environments.

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These linear ridges are beach ridge and swale sequences from St. Phillips Island in South Carolina. The green is

from dense maritime forest that growing near the coast. The light areas in between the ridges are

marshes and the other darker areas between the vegetated ridges are brackish lagoons.Below is a cross

section diagram of near-coast deposits, including beach ridges

Source: Google 2008


Table of Contents

SpitsSpits Spits are elongate depositional landforms that are attached at one end to the Spits are elongate depositional landforms that are attached at one end to the

coast and extend outward from the coast. coast and extend outward from the coast. Spits are formed by a combination of wave and current deposits. As the Spits are formed by a combination of wave and current deposits. As the

waves and current lose energy near the mouth of a bay the sediments waves and current lose energy near the mouth of a bay the sediments deposit as elongate spit landforms. The spit may curve slightly back towards deposit as elongate spit landforms. The spit may curve slightly back towards land in response to the waves refarction pattern hooking back toward the land in response to the waves refarction pattern hooking back toward the land at the end of the spit. land at the end of the spit.

In some cases they may extend outward across the mouth of a bay. If the In some cases they may extend outward across the mouth of a bay. If the spit extends enough sediments to eventually cut off the mouth of the bay it spit extends enough sediments to eventually cut off the mouth of the bay it becomes a bay barrier and the bay becomes a lagoon.becomes a bay barrier and the bay becomes a lagoon.

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This spit is growing towards the southwest and slight curves inland

at the mouth of the inlet. In addition, there is a slight lagoon forming between the coastal area

and the depositional spit landform.

N


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DeltasDeltas

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Deltas form where the mouth of a river meets its ultimate base level at the ocean or sea. As the river’s velocity decreases, it looses the capacity to carry its sediment load and the resulting deposits form a delta. Delta shapes and forms vary depending on tidal influences, waves, currents, sediment type and quantity, river discharge, and the stream gradient near the outlet. The most common types of deltas include bird-foot, estuarine, and arcuate.

Not all rivers form deltas, for example the Amazon deposits its sediment load directly into the ocean onto an underwater seaward sloping continental shelf. The Columbia River in the northwest United States, lacks a delta altogether, because the currents are too strong and erosive for the sediments to deposit. Mississippi River Delta: Bird-Foot Delta A bird-foot delta contains a large

channel with multiple smaller distributary channels draining off

from the main channel and depositing sediments. They generally form with rivers that have a high sediment load and flow into an area with minimal

tidal influences. This false-color infrared image provides a satellite view of the Mississippi River delta.

This delta has shifted positions several times over the last 5000

years in relation to changes in the Mississippi River. Scientist recognize

atleast 7 distinct deltas. The most recent began forming 500 years ago and forms a classic bird-foot delta.


Table of Contents

DeltasDeltas

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The Nile River forms an arcuate fan-shaped delta where it drains into the Mediterranean Sea. It is one of the

largest deltas in the world; however, it is currently disappearing because the upstream Aswan High Dam is storing water and sediments and preventing

them from being deposited in the delta. As a result the delta is eroding and

saltwater is encroaching into freshwater. Other typical arcuate

deltas include the Danube River where it enters the Black Sea in Romania, and

the Ganges and Indus River Deltas flowing into the Bay of Bengal.

Nile River and Arcuate Delta An estuary delta is formed where a river meets the ocean and sediments from the river are filling in the estuary. Estuaries contain a brackish mixture of freshwater

and saltwater, and they have a moderate to strong tidal influence. Estuarine deltas are a common deltaic landform and they occur in

several rivers along the western and eastern United States coasts, the Seine River in

France, and the Tiber River in Italy. The ACE Basin of South Carolina, named for the Ashepoo, Combahee, and Edisto Rivers,

protects nearly 150,00 acres of undeveloped estuary habitat. ACE Basin: Estuarine Delta


Table of Contents

Sea CliffsSea Cliffs Sea cliffs are erosional landforms formed by the undercutting action of the Sea cliffs are erosional landforms formed by the undercutting action of the

sea against the coastline. sea against the coastline. The eroded sea cliff becomes notched inland where the waves erode the The eroded sea cliff becomes notched inland where the waves erode the

coastline and eventually the overhanging land collapses into the ocean. coastline and eventually the overhanging land collapses into the ocean. This process causes the sea cliff to slowly retreat inland eroding more and This process causes the sea cliff to slowly retreat inland eroding more and more of the coastline. more of the coastline.

In undeveloped areas sea cliff related erosion does not pose a hazard. In undeveloped areas sea cliff related erosion does not pose a hazard. Unfortunately extensive areas of the California and Oregon coast are Unfortunately extensive areas of the California and Oregon coast are developed near sea cliffs that are threatened by the erosive force of the developed near sea cliffs that are threatened by the erosive force of the Pacific Ocean.Pacific Ocean.


Source: USGS

These sea cliffs in San Mateo County, California formed from erosive wave action along the

Pacific Ocean. While they create spectacular scenery, they pose a large threat to homeowners that live near the retreating sea-cliff

edge. The u-shaped seaward extension on either side of the

concave eroding sea cliff are referred to as headlands.

HeadlandsHeadlands

Sea cliffSea cliff


Sea ArchSea Arch Sea arches form by erosive wave refraction on opposite sides of a Sea arches form by erosive wave refraction on opposite sides of a

headland.headland. The abrasion from both sides erodes an arch by opening a passageway The abrasion from both sides erodes an arch by opening a passageway

through the headland.through the headland. If the arch erodes to the top of the headland, the seaward extension of the If the arch erodes to the top of the headland, the seaward extension of the

headland becomes isolated from the coastline and forms a sea stack. headland becomes isolated from the coastline and forms a sea stack. In the Hawaiian islands, sea arches maybe linked by pre-existing lava In the Hawaiian islands, sea arches maybe linked by pre-existing lava

tubes that form weakness in the headlands, which erode forming a sea tubes that form weakness in the headlands, which erode forming a sea arch.arch.

In other places, sea arches may form along weaknesses or jointing in the In other places, sea arches may form along weaknesses or jointing in the bedrock. bedrock.

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Sea arch from the Hawaiian Islands

Photo: SCGS


Wave-Cut Scarps and PlatformsWave-Cut Scarps and Platforms Wave cut scarps are erosional cliff-like features formed by sea waves Wave cut scarps are erosional cliff-like features formed by sea waves

breaking against a base of a higher-elevation coastline.breaking against a base of a higher-elevation coastline. The wave-cut platform is a relatively flat bench-like surface that is The wave-cut platform is a relatively flat bench-like surface that is

deposited by the eroded coastline.deposited by the eroded coastline. Wave-cut scarps and platforms often form in a progressive series, relative Wave-cut scarps and platforms often form in a progressive series, relative

to long-term environmental changes, such as sea-level change and or to long-term environmental changes, such as sea-level change and or tectonic uplift. tectonic uplift.

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This wave-cut scarp and platform near Brigden, South Wales was formed by the erosive action of the sea’s waves. The smaller terraces

between the scarp and the current sea-level may eventually form another high-standing platform.

Source: Wikimedia Commons


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Marine TerracesMarine Terraces

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Marine terraces are wave-cut platforms that form a series of terraces that progressively increase in elevation and age away from the modern coastline.

Marine terraces usually form as a result of either sea-level changes, tectonic uplifting, or a combination of both processes.

Marine terrace are composed of shallow to deep marine deposits and often contain fossil remains which provide a method for relative age dating.

Scarps form the boundaries between successive marine terraces and often mark some indicator of landscapes response to environmental changes.The figure below illustrates the sequence of eight marine terraces which form the

Lower Coastal Plain of South Carolina. The oldest terrace sits at an elevation of about 90 feet and the youngest terrace is bound by an active scarp that is being

eroded by high-tide and rising sea-level.


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Continental Shelf and SlopeContinental Shelf and Slope The continental shelf is a submerged extension of the continental crust that The continental shelf is a submerged extension of the continental crust that

slopes gently outward from the modern shoreline to the deep ocean basin. slopes gently outward from the modern shoreline to the deep ocean basin. The continental shelf varies in width from being almost non-existent along The continental shelf varies in width from being almost non-existent along

some continental margins to extending outward for nearly 1500 kilometers some continental margins to extending outward for nearly 1500 kilometers (930 miles) in other places. On average it extends outward for about 80 (930 miles) in other places. On average it extends outward for about 80 kilometers (50 miles) and has an average slope of about 1 degree (2 kilometers (50 miles) and has an average slope of about 1 degree (2 meters/kilometer or 10 feet/mile).meters/kilometer or 10 feet/mile).

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Ocean floor features including continental shelf and slope. This diagram provides a

good illustration of how the shelf is a shallow extension of the continental crust.

A digital elevation model (DEM) of the continental shelf and slope near Los

Angeles, California.

Source: NASA, Visible Earth

Standards: 3-3.5, 3-3.6Standards: 5-3.1, 5-3.2Standards: 8-3.7, 8-3.9

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Deep-Ocean BasinDeep-Ocean Basin The deep ocean basins includes all areas of the ocean beyond the continental The deep ocean basins includes all areas of the ocean beyond the continental

shelf and slope, and excluding mid-ocean ridges. The average depth is 3800 shelf and slope, and excluding mid-ocean ridges. The average depth is 3800 meters (12,500 feet), but varies considerably on account of shallow volcanic meters (12,500 feet), but varies considerably on account of shallow volcanic seamounts and deep trenches.seamounts and deep trenches.

The Pacific Ocean contains the largest ocean basins and accounts for nearly The Pacific Ocean contains the largest ocean basins and accounts for nearly 50% of all salt water on the Earth. The Atlantic Ocean contains the next largest 50% of all salt water on the Earth. The Atlantic Ocean contains the next largest ocean basins, located on either side of the Mid-Atlantic Ridge, and also ocean basins, located on either side of the Mid-Atlantic Ridge, and also contains many shallow seas including the Caribbean, Gulf of Mexico, Baltic, contains many shallow seas including the Caribbean, Gulf of Mexico, Baltic, and Mediterranean. The Arctic and Indian Ocean contain the smallest basins.and Mediterranean. The Arctic and Indian Ocean contain the smallest basins.

The deep ocean basin covers about 30% of Earth’s surface. Trenches, volcanic The deep ocean basin covers about 30% of Earth’s surface. Trenches, volcanic seamounts, and abyssal plains are all part of the deep ocean basin. seamounts, and abyssal plains are all part of the deep ocean basin.

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This map includes a few of the ocean basins in southern hemisphere of the

Atlantic Ocean. The Brazil and Argentina Basin are separated from the Angola

Basin by the Mid-Atlantic Ridge. On the west coast of South America the Pacific

Ocean Basin includes the Peru-Chile Trench, formed by convergent boundary

between the oceanic and continental subduction zone.


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Deep-Ocean Basin FeaturesDeep-Ocean Basin Features Abyssal plains are nearly flat feature-less surfaces are nearly flat feature-less surfaces

and may be the most level areas on Earth. They are and may be the most level areas on Earth. They are very flat because they consist of massive very flat because they consist of massive accumulations of sediment, deposited over the ocean accumulations of sediment, deposited over the ocean floor that bury the underlying topography.floor that bury the underlying topography.

Volcanic seamounts are submerged volcanic are submerged volcanic mountains, either active or inactive. The occasionally mountains, either active or inactive. The occasionally protrude above the surface, exposing their peaks. protrude above the surface, exposing their peaks.

Trenches are deep ocean features were plates are are deep ocean features were plates are submerging into the mantle. Trenches are associated submerging into the mantle. Trenches are associated with volcanic island arcs and areas of intense with volcanic island arcs and areas of intense earthquake activity. Marianas Trench in the South earthquake activity. Marianas Trench in the South Pacific Ocean is the deepest trench, and is more than Pacific Ocean is the deepest trench, and is more than 35,000 feet (10,668 meters), or almost 6.6 miles 35,000 feet (10,668 meters), or almost 6.6 miles (10.6 kilometers) deep. The Navy dove into the (10.6 kilometers) deep. The Navy dove into the deepest part of this trench in January 1960!deepest part of this trench in January 1960!

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The US Navy created this series of cartoon topography to illustrate abyssal plains, trenches, and seamounts.

Source: US Navy, author: Captain Neil F. O'Connor, USN (Ret.)


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Mid-Ocean RidgesMid-Ocean Ridges Mid-ocean ridges are areas of sea-floor spreading along divergent plate Mid-ocean ridges are areas of sea-floor spreading along divergent plate

boundaries. New oceanic crust is formed along the narrow ridge crest, where boundaries. New oceanic crust is formed along the narrow ridge crest, where magma rises and solidifies.magma rises and solidifies.

Mid-ocean ridges are characterized by linear, high elevation ridges, extensive Mid-ocean ridges are characterized by linear, high elevation ridges, extensive faulting, and occasionally volcanic activity. faulting, and occasionally volcanic activity.

The Mid-Atlantic Ridge extends almost the entire length of the North and South The Mid-Atlantic Ridge extends almost the entire length of the North and South Atlantic Ocean and is one of the most prominent subterranean ocean floor Atlantic Ocean and is one of the most prominent subterranean ocean floor features. It rises 3000 meters above the ocean basin floor and is closely features. It rises 3000 meters above the ocean basin floor and is closely monitored by scientists.monitored by scientists.

The Mid-Indian Ridge is another prominent feature, and it is actually a The Mid-Indian Ridge is another prominent feature, and it is actually a continuance of the Mid-Atlantic Ridge system, stretching from below South continuance of the Mid-Atlantic Ridge system, stretching from below South Africa up to India and Egypt. Africa up to India and Egypt.

9898

The USGS created this “baseball” graphic to

illustrate the locations of the major mid-ocean ridge systems. The continuous

line marks the location and orientation of the ridge, and the cross-stitching

represents potential fault patterns along the ridges. Because the ridges mark plate boundaries they are more or less continuous, but are differentiated by name relative to ocean

basin or continental proximity.

Source: USGS, web resources


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Rift ZoneRift Zone Rift zones are fault structures formed by normal faults along active Rift zones are fault structures formed by normal faults along active

boundaries.boundaries. Rising magma below the crust upwells, forcing the lithosphere to fracture, Rising magma below the crust upwells, forcing the lithosphere to fracture,

as it fractures and cracks, one or more faults occur causing the rock layers as it fractures and cracks, one or more faults occur causing the rock layers to separate forming a rift valley. to separate forming a rift valley.

Rift valleys can eventually form lakes or seas such as the Red Sea, which Rift valleys can eventually form lakes or seas such as the Red Sea, which separates Africa from the Arabian Peninsula. separates Africa from the Arabian Peninsula.

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Rift Valleys in Africa

Copyright ©2008 Google Earth

Red Sea

Lake Victoria


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Continental Shelf and Slope:areas of turquoise areas of turquoise colored continental crust colored continental crust around the continental around the continental marginsmargins

Mid-Ocean Ridges: boundary between divergent boundary between divergent plate margins, indicates plate margins, indicates areas of sea-floor spreadingareas of sea-floor spreading

Trenches: deep, narrow features along active deep, narrow features along active margins, trenches are dark blue margins, trenches are dark blue markings located on the map next markings located on the map next to a pink star “ “ to a pink star “ “

Ocean Basin: all of the submerged ocean all of the submerged ocean floor beyond continental floor beyond continental shelf and slope, but shelf and slope, but excluding trenches.excluding trenches.

Rift Zone:tectonically active tectonically active areas of rifting that areas of rifting that create new seascreate new seas

Mid-Atlantic Mid-Atlantic RidgeRidge

Indian RidgeIndian Ridge

East African Rift East African Rift Valley and Red Valley and Red

SeaSea

East Pacific East Pacific RiseRise

Juan de Juan de Fuca RidgeFuca Ridge

Pacific-Antartic Pacific-Antartic RidgeRidge


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Puerto Rico Puerto Rico TrenchTrench

AleutianAleutianTrenchTrench

TongaTongaTrenchTrench

KermadecKermadecTrenchTrench

Central AmericaCentral AmericaTrenchTrench

Peru-ChilePeru-ChileTrenchTrench

South SandwichSouth SandwichTrenchTrench

Java-SundaJava-SundaTrenchTrench

MarianaMarianaTrenchTrench

PhillipinePhillipineTrenchTrench

JapanJapanTrenchTrench

KurilKurilTrenchTrench

Glacial LandformsGlacial Landforms

Ice sheets and Alpine Ice sheets and Alpine GlaciersGlaciers

Ice Field and Ice CapsIce Field and Ice Caps Piedmont GlacierPiedmont Glacier Tidal Glaciers and IcebergsTidal Glaciers and Icebergs Glacial U-shaped ValleysGlacial U-shaped Valleys FjordsFjords Hanging ValleysHanging Valleys Cirques and Cirque GlaciersCirques and Cirque Glaciers ArArêêtes, Horns, Colstes, Horns, Cols Lateral and Medial Lateral and Medial

MorainesMoraines End and Terminal MorainesEnd and Terminal Moraines Paternoster LakesPaternoster Lakes KettlesKettles ErraticsErratics DrumlinsDrumlins Outwash PlainOutwash Plain 101101

Glaciers are large masses of moving ice. Because glaciers are “frozen” they are part of the Earth’s cryosphere, which accounts for 77 percent of all Earth’s freshwater.

Glaciers are very sensitive to the slightest temperature changes. Over Earth’s geologic history the spatial extent and size of glaciers has expanded and shrunk numerous times. As a result, glacial landforms can be found in locations that currently have no active glaciers or glaciation processes. Presently, glacial landforms occur in two distinct geographic regions, high latitude polar environments and high altitude mountain environments. In this section we will explore glacial landforms from their present context and from a historic look into the past.

Copyright ©Bruce Molnia, Terra Photographics

Alpine Valley Glacier in Alaska.


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GlaciersGlaciers Glaciers are large masses of “flowing” ice formed by the accumulation and compaction Glaciers are large masses of “flowing” ice formed by the accumulation and compaction

of recrystallized melted snow. of recrystallized melted snow. Glacial landforms are divided into two broad categories which occur in distinct Glacial landforms are divided into two broad categories which occur in distinct

geographic regions: geographic regions: ice sheets ice sheets which occur high latitude polar environments and which occur high latitude polar environments and alpine glaciers alpine glaciers which occur in high altitude mountain environments.which occur in high altitude mountain environments.

Ice sheetsIce sheets are high latitude polar glaciers that cover extensive areas of continental are high latitude polar glaciers that cover extensive areas of continental landmasses, for this reason they are also referred to as “landmasses, for this reason they are also referred to as “continental glacierscontinental glaciers”. ”. Glacial ice sheet formation requires long periods of extremely low temperatures, Glacial ice sheet formation requires long periods of extremely low temperatures, which allows snow to collect over vast areas covering the underlying terrain. The which allows snow to collect over vast areas covering the underlying terrain. The accumulation of snow forms dense layers that are thousands of meters thick. accumulation of snow forms dense layers that are thousands of meters thick. Antarctica and Greenland are both almost completely covered by glacial ice sheets. Antarctica and Greenland are both almost completely covered by glacial ice sheets.

Alpine glaciersAlpine glaciers are long, linear glaciers that occupy high altitude mountain are long, linear glaciers that occupy high altitude mountain valleys, for this reason they are also referred to as “valleys, for this reason they are also referred to as “valley glaciersvalley glaciers”. Alpine ”. Alpine glaciers flow down valley, and increase in size as they accumulate and absorb glaciers flow down valley, and increase in size as they accumulate and absorb smaller tributary glaciers from the mountainous terrain. Alpine glaciers can be found smaller tributary glaciers from the mountainous terrain. Alpine glaciers can be found all around the world, and presently occur in may of the major mountain ranges in all around the world, and presently occur in may of the major mountain ranges in the world including the Rockies, Andes, and Himalayas. Alpine glaciers may also the world including the Rockies, Andes, and Himalayas. Alpine glaciers may also occur in high-latitude, polar or arctic mountains, such as those in Alaska. occur in high-latitude, polar or arctic mountains, such as those in Alaska.

Geomorphologist’s often refer to glaciers as “rivers of ice” because like rivers, Geomorphologist’s often refer to glaciers as “rivers of ice” because like rivers, continental and alpine glaciers “flow” down-valley through the landscape eroding, continental and alpine glaciers “flow” down-valley through the landscape eroding, transporting, and depositing weathered materials along their the path. It is this transporting, and depositing weathered materials along their the path. It is this combination processes that forms the diverse array of constructive and destructive combination processes that forms the diverse array of constructive and destructive glacial landforms. glacial landforms.

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Ice Sheets and Alpine Ice Sheets and Alpine GlaciersGlaciers

An ice sheet is a continuous widespread, An ice sheet is a continuous widespread, mass of glacial ice which blankets the entire mass of glacial ice which blankets the entire landscape, and in their most extensive form, landscape, and in their most extensive form, ice sheets may cover an entire continent. It is ice sheets may cover an entire continent. It is estimated that 90 percent of Antarctica and estimated that 90 percent of Antarctica and nearly 80 percent of Greenland are covered nearly 80 percent of Greenland are covered

by ice sheets. Both of these ice sheets are so by ice sheets. Both of these ice sheets are so thick, that portions the Earth’s crust below thick, that portions the Earth’s crust below

them are isostatically depressed, placing the them are isostatically depressed, placing the actual landmass thousands of feet below sea-actual landmass thousands of feet below sea-

level. As the ice melts and the weight is level. As the ice melts and the weight is removed, the landmass will slowly rebound removed, the landmass will slowly rebound

and rise back up to sea-level. Both the and rise back up to sea-level. Both the Antarctic Ice Sheet and Greenland Ice Sheet Antarctic Ice Sheet and Greenland Ice Sheet are over 9800 feet thick in some places, and are over 9800 feet thick in some places, and the only landmasses exposed are the highest the only landmasses exposed are the highest

elevation mountain peaks. elevation mountain peaks. 103103

Glacier National Park in the United States has been sculpted by alpine glacial processes

over thousands of years. Today, Glacier NP’s landscape contains vestiges of past

glaciation, with only a few active, high elevation alpine glaciers. Recent temperature increases are melting glaciers at an alarming rate. Scientist predict that by 2030 there may not be any more glaciers in Glacier National

Park! The images below taken from the same location, 67 years apart, shows the effects of

climate change on glaciers.

Antarctic Ice Sheet Antarctic Ice Sheet

19381938 20052005

Source: USGS


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This aerial image of the Vatnajökull Ice Cap in Iceland has several glaciers flowing

outward from the ice cap. NASA scientists monitor the effects of global warming on

this ice cap using satellite imagery. Notice how the advancing glaciers are slightly

darker colored than the ice sheet from the sediments and debris they are transporting.

Ice Field and Ice CapsIce Field and Ice Caps

104104

Ice fields Ice fields are elongate, continuous expanses of glacial ice which follow are elongate, continuous expanses of glacial ice which follow the topography of mountains. Isolated mountain ridges and peaks often the topography of mountains. Isolated mountain ridges and peaks often protrude out from the ice field. Ice field may feed alpine glaciers. protrude out from the ice field. Ice field may feed alpine glaciers.

Ice caps Ice caps are circular shaped masses of glacial ice that cover an area are circular shaped masses of glacial ice that cover an area less than 50,000 kmless than 50,000 km22. Ice caps form in mountain regions and they . Ice caps form in mountain regions and they completely bury the underlying topography. Ice caps are similar to ice completely bury the underlying topography. Ice caps are similar to ice sheets, only smaller.sheets, only smaller.

The high altitude environments in Alaska contain large ice fields that feed alpine glaciers. In this picture,

you can see the mountain peaks protruding above the ice field. This

image also contains example of crevasses, or cracks, in glacial ice.

Copyright ©Bruce Molnia, Terra Photographics Source: wikimedia commons, NASA image


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Piedmont GlacierPiedmont Glacier Piedmont glaciers are formed where multiple valley glaciers flow Piedmont glaciers are formed where multiple valley glaciers flow

out from the mountainous terrain and coalesce into a singe large out from the mountainous terrain and coalesce into a singe large glacier, spreading over the lowland topography.glacier, spreading over the lowland topography.

Piedmont glaciers continue to grow as long as they are fed by Piedmont glaciers continue to grow as long as they are fed by valley glaciers. Piedmont glaciers often source rivers and streams valley glaciers. Piedmont glaciers often source rivers and streams that form from glacial melt water and till deposits. that form from glacial melt water and till deposits.

105105

This piedmont glacier is part of the Malaspina Glacier in Alaska

and is the largest piedmont glacier in the United States. The Mount Saint Elias mountains in the background are the source that feed this piedmont glacier.

The dark bands in the photo mark the lateral and medial moraines where the valley glaciers merged together.



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Tidal Glaciers and IcebergsTidal Glaciers and Icebergs Tidal glaciers are the portion of either alpine or continental glaciers Tidal glaciers are the portion of either alpine or continental glaciers

which spill out into the sea and float on the surface of the saltwater.which spill out into the sea and float on the surface of the saltwater. The glacial ice over the water breaks by calving off into large icebergs. The glacial ice over the water breaks by calving off into large icebergs. Icebergs are large floating blocks of ice that calved off from tidal Icebergs are large floating blocks of ice that calved off from tidal

glaciers. glaciers. Icebergs usually calve off along crevasses or cracks in the ice, but can Icebergs usually calve off along crevasses or cracks in the ice, but can

also fail from a combination of melting and gravitational pull. also fail from a combination of melting and gravitational pull. Icebergs vary in size and thickness, and some reach heights more than Icebergs vary in size and thickness, and some reach heights more than

100 feet!100 feet!

106106

The icebergs in the front of the photo calved of from the

tidal glacier in the background. The portion of the icebergs exposed above

the water is often only a third of their entire size, the

other two-thirds is submerged below the water.



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Glacial “U-Shaped” ValleysGlacial “U-Shaped” Valleys Glacial valleys are formed by the abrasive action of glacial ice as it Glacial valleys are formed by the abrasive action of glacial ice as it

slowly carves a “u-shaped” path through the mountainous valleys. slowly carves a “u-shaped” path through the mountainous valleys. Prior to the formation of the glacier, most valleys are initially formed as a Prior to the formation of the glacier, most valleys are initially formed as a

“v-shaped” stream valley eroded by flowing water. Once the valleys “v-shaped” stream valley eroded by flowing water. Once the valleys becomes occupied by the glacier, the glacial ice spreads from one side of becomes occupied by the glacier, the glacial ice spreads from one side of the valley to the other, completely filling in the valley floor and up the the valley to the other, completely filling in the valley floor and up the hill slopes. As the glaciers moves down-valley it abrasively erodes the hill slopes. As the glaciers moves down-valley it abrasively erodes the pre-formed “v-shaped” stream valley into a “u-shaped” glacial valley. pre-formed “v-shaped” stream valley into a “u-shaped” glacial valley.

107107

The Alaska's Woodworth Glacier, on the left is beginning to retreat and expose a

glacial u-shaped valley beneath the melting ice. The Sierra Nevada landscape with Yosemite Valley

pictured below, presently only contains glaciers in the highest elevations, but

many of the prominent u-shaped valleys, reveal past evidence of glacial

erosion.

Copyright ©Bruce Molnia, Terra PhotographicsSource: Wikimedia Commons


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FjordsFjords Fjords are flooded troughs that form where glacial u-shaped valleys Fjords are flooded troughs that form where glacial u-shaped valleys

intersect the ocean and the sea floods inland filling up the valley. intersect the ocean and the sea floods inland filling up the valley. Fjords can form during active glaciation or post-glaciation depending on Fjords can form during active glaciation or post-glaciation depending on

sea-level. sea-level. When a glacier intersects the ocean, the glacier can continue to erode and When a glacier intersects the ocean, the glacier can continue to erode and

carve the valley below sea-level. The water that fills in above the glacier carve the valley below sea-level. The water that fills in above the glacier and floods the valley forms a fjord.and floods the valley forms a fjord.

Fjords can also form post-glaciation by rising sea-level or changes in Fjords can also form post-glaciation by rising sea-level or changes in elevation along the coastline from melting ice.elevation along the coastline from melting ice.

108108Copyright © Michael Collier, USGS

On the left is a glacier intersecting a fjord in the Pacific Ocean off Estero de las Montanas in Chile,

South America. Below is an aerial view of the Prince William Sound and Cascade Glacier fjord

in Alaska.

Copyright © 2008 Google


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Hanging ValleysHanging Valleys Hanging valleys are abrupt, cliff-like features that are formed at the Hanging valleys are abrupt, cliff-like features that are formed at the

confluence where smaller tributary glaciers merge with larger valley glaciers.confluence where smaller tributary glaciers merge with larger valley glaciers. The scour of the larger glacier carves the valley into a u-shape, removing the The scour of the larger glacier carves the valley into a u-shape, removing the

original gradient of the tributary confluence, as a result the tributary valley is original gradient of the tributary confluence, as a result the tributary valley is left stranded or “hanging” above the larger valley.left stranded or “hanging” above the larger valley.

Hanging valleys are only visible after the glacier melts and reveals the Hanging valleys are only visible after the glacier melts and reveals the underlying topography. Hanging valleys are often the sight of dramatic underlying topography. Hanging valleys are often the sight of dramatic plunging waterfalls. plunging waterfalls.

109109Copyright ©Bruce Molnia, Terra Photographics

These images show hanging valleys in two These images show hanging valleys in two different periods. Below the tributary glacier different periods. Below the tributary glacier is retreating and a waterfall begins to form. is retreating and a waterfall begins to form. The image on the right is of a post-glacial The image on the right is of a post-glacial hanging valley, Bridal Falls in Yosemite hanging valley, Bridal Falls in Yosemite

National Park.National Park.

Hanging Valley


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Cirques and Cirque GlaciersCirques and Cirque Glaciers Cirques are bowl-shaped eroded, depressions near-mountain top ridges Cirques are bowl-shaped eroded, depressions near-mountain top ridges

where snow accumulates and forms the head of an alpine glacier. where snow accumulates and forms the head of an alpine glacier. Glaciers in this early phase of formation are often referred to as cirque Glaciers in this early phase of formation are often referred to as cirque

glaciers. The confluence of multiple cirque glaciers merges to form a glaciers. The confluence of multiple cirque glaciers merges to form a valley glaciers. Cirque glaciers feed valley glaciers a relatively steady valley glaciers. Cirque glaciers feed valley glaciers a relatively steady source of new snow.source of new snow.

When glaciers retreat, the cirque is often the last part of the glacier to When glaciers retreat, the cirque is often the last part of the glacier to melt. melt.

110110

Cirque GlaciersCirque Glaciers


Mount Fairweather in Alaska Mount Fairweather in Alaska contains several cirques glaciers contains several cirques glaciers

that feed into valley glaciers that feed into valley glaciers that descend down the that descend down the

mountain. This image shows two mountain. This image shows two different cirque glaciers of different cirque glaciers of

varying sizes feeding different varying sizes feeding different valley glaciers separated by cols valley glaciers separated by cols

and arêtes. In post glacial and arêtes. In post glacial landscapes, cirques may fill with landscapes, cirques may fill with

water to form cirque lakes. water to form cirque lakes.


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ArArêêtes Cols and Hornstes Cols and Horns ArArêêtestes are saw-tooth, serrated ridges in glacial mountains. Arare saw-tooth, serrated ridges in glacial mountains. Arêêtes tes

separate adjacent cirques and adjacent valleys. Arseparate adjacent cirques and adjacent valleys. Arêête is French for te is French for “knife-edge”, and the ridges are appropriately named!“knife-edge”, and the ridges are appropriately named!

ColsCols form when two cirque basins on opposite sides of the mountain form when two cirque basins on opposite sides of the mountain erode the arerode the arêête dividing them. Cols create saddles or passes over te dividing them. Cols create saddles or passes over the mountain. the mountain.

HornsHorns are a single pyramidal peak formed when the summit is are a single pyramidal peak formed when the summit is eroded by cirque basins on all sides. Horns form majestic mountain eroded by cirque basins on all sides. Horns form majestic mountain peaks and create many challenges for adventurous climbers. peaks and create many challenges for adventurous climbers. Matterhorn, in the Swiss Alps, is a well known horn. Matterhorn, in the Swiss Alps, is a well known horn.

111111Copyright ©Bruce Molnia, Terra Photographics

HornHornArêteArête

ColCol

On the left is a classic set of glacial On the left is a classic set of glacial landforms in the Chugach Mountains, landforms in the Chugach Mountains, Alaska. Many of the glaciers in this Alaska. Many of the glaciers in this range are currently retreating and range are currently retreating and

exposing the erosive action of the glacial exposing the erosive action of the glacial ice on the landscape. Below is the ice on the landscape. Below is the

famous Matterhorn in the Swiss Alps.famous Matterhorn in the Swiss Alps.

Source; Wikimedia commons


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Lateral and Medial MorainesLateral and Medial Moraines Moraines are formed by the deposition of Moraines are formed by the deposition of

glacial till as the glacier melts. Moraines are glacial till as the glacier melts. Moraines are defined by where the glacial till was deposited defined by where the glacial till was deposited relative to the moving, melting glacier.relative to the moving, melting glacier.

The four most common moraine types areThe four most common moraine types are laterallateral, , medialmedial, , endend, and , and terminalterminal moraines. moraines.

Lateral moraines Lateral moraines are long linear ridges of are long linear ridges of glacial till deposited along the side of the glacial till deposited along the side of the glacier parallel to its direction of movement. glacier parallel to its direction of movement.

Medial moraines Medial moraines are long linear ridges that are long linear ridges that form along the contact where tributary glaciers form along the contact where tributary glaciers with lateral moraines merge to join larger with lateral moraines merge to join larger valley glaciers. Medial moraines form were the valley glaciers. Medial moraines form were the glaciers merge together the till deposits glaciers merge together the till deposits become incorporated as dark ridges of become incorporated as dark ridges of sediment oriented down valley and aligned sediment oriented down valley and aligned parallel through the middle of the glacier. parallel through the middle of the glacier.

112112

Kennicott Glacier shows off Kennicott Glacier shows off multiple medial moraines as it multiple medial moraines as it

descends Mount Blackburn in the descends Mount Blackburn in the Wrangell-St. Elias National Park in Wrangell-St. Elias National Park in

Alaska.Alaska.

Copyright © Michael Collier, USGS


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Terminal and End MorainesTerminal and End Moraines

113113

View of the retreating Schwan Glacier in View of the retreating Schwan Glacier in the Chugach Mountains of Alaska. The the Chugach Mountains of Alaska. The terminus is marked by an outwash plain terminus is marked by an outwash plain and lake formed from the melting snow. and lake formed from the melting snow. This image contains many classic glacial This image contains many classic glacial

features, including u-shaped valleys, features, including u-shaped valleys, hanging valleys, arêtes, and end, terminal, hanging valleys, arêtes, and end, terminal,

medial, and lateral moraines. medial, and lateral moraines.

Copyright © Bruce Molnia, Terra Photographics

Terminal moraines Terminal moraines are linearare linear, , concave, arc-shaped depositional concave, arc-shaped depositional ridges that form at the terminus ridges that form at the terminus of a glacier. The terminal moraine of a glacier. The terminal moraine is formed by the deposits of glacial is formed by the deposits of glacial till that mark the outward expanse till that mark the outward expanse or limit of glacial movement . Even or limit of glacial movement . Even if the glacier is no longer if the glacier is no longer advancing forward, it continues to advancing forward, it continues to transport ice and sediments to the transport ice and sediments to the terminus, where the ice melts and terminus, where the ice melts and the sediments bound up in the ice the sediments bound up in the ice are deposited as the terminal are deposited as the terminal moraine. moraine.

End morainesEnd moraines, also referred to as , also referred to as recessional moraines, are concave recessional moraines, are concave arc-shaped ridges deposited by arc-shaped ridges deposited by the melting glacier. They are the melting glacier. They are similar to terminal moraines, similar to terminal moraines, except that they are generally except that they are generally smaller, and they mark the smaller, and they mark the gradual retreat of the glacial ice gradual retreat of the glacial ice after it has already deposited its after it has already deposited its terminal moraine. terminal moraine.


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Paternoster LakesPaternoster Lakes Patternoster lakes are a connected string of small, circular lakes that Patternoster lakes are a connected string of small, circular lakes that

occur in valleys previously occupied by glaciers. occur in valleys previously occupied by glaciers. Patternoster lakes are post glacial erosional features filled with Patternoster lakes are post glacial erosional features filled with

rainwater or glacial meltwater. rainwater or glacial meltwater. The depressions where the lakes form are usually the result of either The depressions where the lakes form are usually the result of either

differential erosion of the bedrock, or the creation of small dams formed differential erosion of the bedrock, or the creation of small dams formed by glacial till deposits or end moraines. by glacial till deposits or end moraines.

Initially, melted glacial ice fills the depressions creating a string of lakes. Initially, melted glacial ice fills the depressions creating a string of lakes. Over time, precipitation or springs provide a renewable source of Over time, precipitation or springs provide a renewable source of freshwater. freshwater.

114114

This string of patternoster lakes in this u-shaped valley

in the Sierra Nevada Mountains of California

provides evidence of past glaciations. Glaciers have

occupied this valley on and off over the last 2.5 million years during cooler ice age

periods. Glaciers may occupy these valleys again in the

future.



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KettlesKettles Kettles are small depressions in the landscape, often filled with water, Kettles are small depressions in the landscape, often filled with water,

that form post-glaciation. that form post-glaciation. Kettles form when large blocks of ice are left by a retreating glacier Kettles form when large blocks of ice are left by a retreating glacier

and the land surrounding the abandoned ice block accretes from the and the land surrounding the abandoned ice block accretes from the accumulation of glacial deposits. After the ice block melts, only a void accumulation of glacial deposits. After the ice block melts, only a void or kettle remains. or kettle remains.

The kettle can also be deepened by the melting and subsidence of the The kettle can also be deepened by the melting and subsidence of the ground below where the ice block previously lay. ground below where the ice block previously lay.

Kettles formation is most common where glaciers retreat from the Kettles formation is most common where glaciers retreat from the steep terrain and flow into lower-lying valleys. steep terrain and flow into lower-lying valleys.

Kettles may or may not form lakes. Those that contain water are often Kettles may or may not form lakes. Those that contain water are often sourced by rainfall or snowmelt. sourced by rainfall or snowmelt.

115115

This small kettle was formed by the melting and retreat of glacial ice from this valley. The kettle is

surrounded by a small ridge formed by the deposition of

glacial till from the melting ice block. The presence of plants in

the forefront of the image suggest that glaciers have been absent from this area for at least

a couple decades and maybe longer.



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ErraticsErratics Erratics are large, isolated boulders deposited by retreating, melting Erratics are large, isolated boulders deposited by retreating, melting

glaciers. They are post-glacial depositional features that provide evidence glaciers. They are post-glacial depositional features that provide evidence of past glaciations. of past glaciations.

As glaciers move across the landscape they pick up sediments by plucking As glaciers move across the landscape they pick up sediments by plucking them off the surface. This process incorporates sediments into the glacial them off the surface. This process incorporates sediments into the glacial ice and transports them down-valley. When the glacier melts, these ice and transports them down-valley. When the glacier melts, these sediments are deposited. Erratics, are generally the largest rocks left sediments are deposited. Erratics, are generally the largest rocks left behind by the retreating glaciers. They are generally smooth from glacial behind by the retreating glaciers. They are generally smooth from glacial abrasion and appear “misplaced” in the landscape. abrasion and appear “misplaced” in the landscape.

116116Source: Wikimedia Commons

Yosemite Valley is littered with glacial erratics, like the example

below, perched on Lambert Dome. This erratic is quite angular

suggesting it was only transported by the glacier for a short distance or

amount of time.

The image above is from a recently deposited glacial erratic. Notice how

the erratic is still perched atop glacial ice, and there is a glacier retreating in

the lower right corner of the image. The person in front of the erratic provides a

relative scale for size.


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DrumlinsDrumlins Drumlins are long, linear hills of glacial till deposited by ice sheets. The term Drumlins are long, linear hills of glacial till deposited by ice sheets. The term

“drumlin” comes from the Irish word “druim” which translates to ridge.“drumlin” comes from the Irish word “druim” which translates to ridge. Drumlins are similar to medial and lateral moraines, except that they are Drumlins are similar to medial and lateral moraines, except that they are

usually smaller and may be irregular shaped relative to the direction of usually smaller and may be irregular shaped relative to the direction of glacial movement. Drumlin fields are areas with numerous drumlins.glacial movement. Drumlin fields are areas with numerous drumlins.

117117Source: Wikimedia Commons

The digital elevation model (DEM) on the right shows a large drumlin field with

numerous drumlins all oriented in the same direction. Below is a photo of a drumlin

overgrown with vegetation. Both of these examples are from New York, where

extensive glacial ice sheets once covered the northeast United States.

Source: Wikimedia Commons


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Outwash Plains and EskersOutwash Plains and Eskers Glacial outwash plains are extensive stratified deposits of glacial till Glacial outwash plains are extensive stratified deposits of glacial till

below a glacier that usually form braided streams. They are choked with below a glacier that usually form braided streams. They are choked with glacial till and are fed by melt-water flowing from the base of the glacier.glacial till and are fed by melt-water flowing from the base of the glacier.

Outwash plains form a complicated network of braided channels, flowing Outwash plains form a complicated network of braided channels, flowing through a mess of glacial till sediment deposits. The streams partially through a mess of glacial till sediment deposits. The streams partially sort the mess of sediments, transporting the finer materials further sort the mess of sediments, transporting the finer materials further downstream and leaving behind the coarser till deposits. downstream and leaving behind the coarser till deposits.

Eskers form along melt water channels that are emerging from tunnels Eskers form along melt water channels that are emerging from tunnels beneath the glacier. They are depositional ridges of sands and gravel beneath the glacier. They are depositional ridges of sands and gravel that mark the “course” of the melting glacier or course of the melt water that mark the “course” of the melting glacier or course of the melt water tunnel. tunnel.

Eskers form interesting sinuous ridges across a landscape marking the Eskers form interesting sinuous ridges across a landscape marking the location of a melt water tunnels from a glacier. location of a melt water tunnels from a glacier.

118118

The outwash plain below this glacier in the left image heads a braided river that

flows through the glacial till deposits. The image below contains recently

formed eskers exposed by the melted glacier.



Table of Contents

South Carolina Earth Science South Carolina Earth Science Education Standards: Grade 3Education Standards: Grade 3

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Earth’s Materials and Changes:Earth’s Materials and Changes:

Standard 3-3Standard 3-3:The student will demonstrate an understanding of Earth’s composition :The student will demonstrate an understanding of Earth’s composition and theand the

changes that occur to the features of Earth’s surface. (Earth Science).changes that occur to the features of Earth’s surface. (Earth Science).

Indicators:Indicators:3-3.5: Illustrate Earth’s saltwater and freshwater features (including oceans, seas, rivers,

lakes, ponds, streams, and glaciers). 3-3.6: Illustrate Earth’s land features (including volcanoes, mountains, valleys, canyons,

caverns, islands) by using models, pictures, diagrams, and maps.3-3.8: Illustrate changes in Earth’s surface that are due to slow processes (including

weathering, erosion, and deposition) and changes that are due to rapid processes (including landslides, volcanic eruptions, floods, and earthquakes).

Table of Contents



Landforms and Oceans:Landforms and Oceans:

Standard 5-3: Standard 5-3: The student will demonstrate an understanding of features, processes, The student will demonstrate an understanding of features, processes, and changes in Earth’s land and oceans. (Earth Science)and changes in Earth’s land and oceans. (Earth Science)

Indicators: Indicators:

5-3.1: 5-3.1: Explain how natural processes (including weathering, erosion, deposition, Explain how natural processes (including weathering, erosion, deposition, landslides, volcanic eruptions, earthquakes, and floods) affect Earth’s oceans and landslides, volcanic eruptions, earthquakes, and floods) affect Earth’s oceans and land in constructive and destructive ways.land in constructive and destructive ways.

5-3.2: 5-3.2: Illustrate geologic landforms of the ocean floor (including the continental shelf and slope, the mid-ocean ridge, rift zone, trench, and ocean basin).

5-3.4: 5-3.4: Explain how waves, currents, tides, and storms affect the geologic features of the Explain how waves, currents, tides, and storms affect the geologic features of the ocean shore zone (including beaches, barrier islands, estuaries, and inlets). ocean shore zone (including beaches, barrier islands, estuaries, and inlets).

5-3.5: 5-3.5: Compare the movement of water by waves, currents, and tides.Compare the movement of water by waves, currents, and tides.



Earth’s Structure and ProcessesEarth’s Structure and Processes

Standard 8-3: Standard 8-3: The student will demonstrate an understanding of materials that determine the structure of Earth and the processes that have altered this structure. (Earth Science)

Indicators:8-3.7: Illustrate the creation and changing of landforms that have occurred through

geologic processes (including volcanic eruptions and mountain building forces).8-3.9: Identify and illustrate geologic features of South Carolina and other regions of the

world through the use of imagery (including aerial photography and satellite imagery) and topographic maps.

Resources and ReferencesResources and References


Christopherson, R. W. 2004. Elemental Geosystems. 4th Ed. Prentice Hall. Upper Saddle River, New Jersey.

Lutgens, F. K. and E. J. Tarbuck 2003. Essentials of Geology, 8th Ed. Prentice Hall. Upper Saddle River, New Jersey.

Smith, G. A. and Pun, A. 2006. How does Earth Work? Physical Geology and the Smith, G. A. and Pun, A. 2006. How does Earth Work? Physical Geology and the Process of Science. Process of Science. Prentice Hall. Upper Saddle River, New Jersey.

Topography, Landforms, and Geomorphology Designed to meet South Carolina Department of Education...

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