LANDFORMS AND LANDFORMS AND OCEANSOCEANS

Science Standard 5-3Science Standard 5-3The student will demonstrate an The student will demonstrate an

understanding of features, understanding of features, processes, and changes in Earth's processes, and changes in Earth's

land and oceans. land and oceans.

5-3.1 Explain how natural 5-3.1 Explain how natural

processes (including weathering, processes (including weathering,

erosion, deposition, landslides, erosion, deposition, landslides,

volcanic eruptions, earthquakes, volcanic eruptions, earthquakes,

and floods) affect Earth's oceans and floods) affect Earth's oceans

and land in constructive and and land in constructive and

destructive ways.destructive ways.

What are constructive

forces?

Constructive forces are processes that create or build up

landforms.

What are destructive

forces?

Destructive forces are processes that

destroy or wear down landforms.

What are some

examples of

landforms?

pinker.wjh.harvard.edu/.../Grand%20Canyon.htm

gsbwww.uchicago.edu/.../porcupines.html

media.vacationeasttennessee.org/pfoutdoorattr...

Two ForcesTwo Forces• Constructive:

Building up an existing landform or forming a new one

•Destructive: Changing or destroying an existing landform.

This building is being CONSTRUCTED. This building is being DESTRUCTED.

What are natural processes?

How do they affect land and oceans?

WeatheringWeathering

This is a destructive force and

can be chemical or physical. It

causes the surface of the earth

to dissolve, decompose, and

break into smaller pieces.

WeatheringWeathering• Weathering: A slow, destructive

process that breaks rocks into smaller pieces called sediment.

ErosionErosion

This is a destructive force. It is

the movement of sediments

and soil by wind, water, and

gravity.

ErosionErosion

• The movement of materials away from one place.

• Erosion is destructive.

ErosionTune: "Jingle Bells"

Running down a hillOr coming down as snow,

Water causes muchErosion, this we know.

Wave action moves the beach.A river carves the land.

Everywhere that water goes,It Carries dirt or sand.

  Chorus:

Oh, wind and rain, snow and ice,

Water running free;These all cause land to erode

With changes we can see.Wind and rain, snow and ice,

Water running free;These all cause land to erode

With changes we can see .  

Wind blowing in a gale,Or as gentle as a breeze,

Wears the rock away,And carries sand with ease.

A hurricane last year,And glaciers long ago,

Are ways that natural forces use

To change the earth we know. (Repeat Chorus)

DepositionDeposition

This is a constructive force. It

builds up new land by dropping

or depositing sediments via

water, wind, or ice.

LandslideLandslide

This is a destructive force. This

is a mass movement of land

due to gravity. Landslides even

occur in the ocean on the

continental slope.

LandslideLandslide

Landslides

can cause

buildings to

fall, or power

and gas lines

to break.

Volcanic EruptionVolcanic Eruption

This is a constructive force. During

an eruption, melted rock rises

from deep within the earth and

reaches the surface. They can

also occur under the oceans.

Volcanic EruptionVolcanic Eruption

Seamounts are

volcanoes

that are built

up under the

ocean.

EarthquakeEarthquake

This is a destructive force.

Earthquakes are vibrations or a

shaking of the ground caused

by energy that is released from

the Earth’s crust.

EarthquakeEarthquake

Earthquakes under the ocean

can cause huge waves

(tsunamis) that cause great

damage if they come ashore.

FloodFlood

This is both a destructive force and a

constructive force. Floods occur

when a large amount of water

covers land that is normally dry.

Rapid erosion can take place, but

new sediment is left behind when

the water recedes.

5-3.2 Illustrate the geologic 5-3.2 Illustrate the geologic

landforms of the ocean floor: landforms of the ocean floor:

*continental shelf *continental shelf

*continental slope *continental slope

*mid-ocean ridge *mid-ocean ridge

*rift zone *rift zone

*trench *trench

*ocean basin *ocean basin

Journey to Bottom of the Journey to Bottom of the OceanOcean

We will begin our journey where land meets the ocean.

Do you know where we are?

Yes. At the beach.

Beaches are the fastest changing part of the ocean. They change with every wave.

Continental ShelfContinental Shelf• The continental shelf is where the edge of the

continent slopes down from the shore into the ocean. • It is the part of the continent located under water. • It is not the deepest part

of the ocean.

Continental SlopeContinental Slope• The continental slope is a steep drop-off

at the edge of the shelf.

• It drops to the bottom of the ocean floor, making the water much deeper.

Mid-Ocean RidgesMid-Ocean Ridges• A mountain range on the ocean floor.

• Some of these mountains are volcanic.

• Volcanic mountains that ARE NOT found on the mid-ocean ridges are called seamounts.

For more information on the ridges, visit http://www.waterencyclopedia.com/Mi-Oc/Mid-Ocean-Ridges.html

Rift ZoneRift Zone• In the center of the highest part of the mid-

ocean ridge is a narrow trench called a rift.

• Underwater volcanic activity that adds mountains to either side of the mid-ocean ridge occurs at the rift zone.

Ocean TrenchOcean Trench• The ocean trench is a steep sided canyon or

deep narrow valley in the bottom of the ocean. • Trenches are the deepest part of the ocean

basin and deeper than any valley found on land.

Ocean BasinOcean Basin• The ocean basin is located on either side

of the mid-ocean ridge.

• It is made up of low hills and flat plains.

• The flat area of the basin is called the abyssal plains.

• This is where seamounts are generally formed.

Seamount Seamount

• These are volcanic mountains not formed on the mid-ocean ridge.

5-3.3 Compare continental and 5-3.3 Compare continental and

oceanic landforms. oceanic landforms.

Earth is made of solid land. Earth is made of solid land.

Some of the land is located Some of the land is located

above Earth’s water and some above Earth’s water and some

is located below the oceans.is located below the oceans.

Explain how landforms above Explain how landforms above

the oceansthe oceans are similar to are similar to

those found below the oceans.those found below the oceans.

Continental Landform

Oceanic Landform

Canyon Trench

Valley Rift

Volcano Seamount

Mountain range Mid-ocean ridge

Low hills or plainsOcean basin and

abyssal plain

5-3.4 Explain how waves, 5-3.4 Explain how waves,

currents, tides, and storms affect currents, tides, and storms affect

the geologic features of the the geologic features of the

ocean shore zone (including ocean shore zone (including

beaches, barrier islands, beaches, barrier islands,

estuaries, and inlets). estuaries, and inlets).

BeachesBeaches

http://www.virtualtourist.com/travel/North_America/United_States_of_America/South_Carolina/Charleston-864816/Things_To_Do-Charleston-Beaches-BR-1.html

The shoreline, or coast, is the

area where the land meets the

ocean. Some shorelines are

rocky. Shorelines made of sand

are called beaches. Shorelines

are always changing because of

wind and water.

Waves can wear away the land and expose a rocky shore or the

waves can deposit sand along the shore and form a beach. If the waves reach the beach at an

angle, the sand is moved along the coast.

Currents, called longshore currents, along the shoreline can move sand from one location to

another.

Tides can bring in sand, shells, and ocean sediments at high tide and leave them behind when the

tide goes out.

Barrier IslandsBarrier Islands

www.dnr.sc.gov/.../river/stewardship_gallery.htm

Islands are pieces of land surrounded by water on all sides. Islands with sandy beaches are

called barrier islands.

These barrier islands are naturally occurring and function to protect the mainland from the effects of

waves on its shore. As the waves deposit sand on the beaches, the

shapes of the barrier islands change.

Currents can move the sand from

one end of the island to the other.

EstuariesEstuaries

serc.carleton.edu/.../northinlet/index.html

All rivers flow into the oceans. The area where a river meets the

ocean is known as an estuary. Estuaries have a mixture of freshwater and saltwater.

Waves can deposit sand in the estuaries. At high tide ocean

water brings in sediments and sea life that feed and nourish life

in the estuary.

InletsInlets

www.ncsu.edu/.../sc/hunting2/hunting2.html

Inlets are the water-filled spaces between the barrier islands.

As the tides change, the amount of water in the inlet will change.

Ocean currents and storms can change the shape of an inlet

opening.

Large storms, for example hurricanes, can also cause massive destruction to the

shape of the beaches, barrier islands, estuaries, and inlets because they produce high waves and heavy winds.

5-3.5 Compare the 5-3.5 Compare the

movement of water by waves, movement of water by waves,

currents, and tides. currents, and tides.

Volcanoes And EarthquakesVolcanoes And Earthquakes

This map shows how volcanoes and earthquakes occur along tectonic plate boundaries.http://www.pbs.org/wgbh/nova/teachers/activities/2515_vesuvius.html

http://www.mos.org/oceans/planet/features.html

ResourcesResources

Magic School Bus Blows Its Top, The. Scholastic. 1995.unitedstreaming. 13 September 2006<http://www.unitedstreaming.com/> (23:56)