Post on 20-Apr-2018
Chapter 3 Patterns in Nature:
Minerals
1
Essentials of Geology, 4th edition by Stephen Marshak © 2013 W.W. Norton & Company
PowerPoint slides prepared by Rick Oches, Professor of Geology & Environmental Sciences, Bentley University, Waltham, Massachusetts
By Stephen Altaner (Univ. of Illinois)
GEOL 100 (Planet Earth) Topic #7 - The Rock Cycle
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Rock Definition Rock = coherent, relatively hard, naturally formed mass of mineral matter
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Importance of Rocks • Natural Hazards - Volcanoes, sinkholes, landslides
are directly linked to rock
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Importance of Rocks • Natural Hazards - Damage from floods, earthquakes
is related to bedrock type
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Importance of Rocks • Natural Resources - Rock
US Production of Crushed Stone, Sand, Gravel - Projected to 2020
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Importance of Rocks • Natural Resources - energy (oil, coal, natural gas)
Chapter 3 Patterns in Nature:
Minerals
2
Essentials of Geology, 4th edition by Stephen Marshak © 2013 W.W. Norton & Company
PowerPoint slides prepared by Rick Oches, Professor of Geology & Environmental Sciences, Bentley University, Waltham, Massachusetts
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Importance of Rocks • Natural Resources - Groundwater
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Importance of Rocks • Natural Resources - Groundwater
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Importance of Rocks • Geologic History
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Rock Characterization Rocks are characterized based on: 1) Mineral content 2) Texture - size (large = coarse-grained; small, microscopic =
fine-grained), shape, arrangement of mineral grains (aligned or random).
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Classes of Rocks - Igneous Form by cooling and solidification of hot molten rock, which can cool at Earth's surface (extrusive igneous rock) or below Earth's surface (intrusive igneous rock)
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Classes of Rocks - Igneous Typical texture = interlocking with random arrangement, no space between grains similar to jigsaw puzzle
Chapter 3 Patterns in Nature:
Minerals
3
Essentials of Geology, 4th edition by Stephen Marshak © 2013 W.W. Norton & Company
PowerPoint slides prepared by Rick Oches, Professor of Geology & Environmental Sciences, Bentley University, Waltham, Massachusetts
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Classes of Rocks - Sedimentary Most form by hardening (lithification) of layers of sediment (loose grains of preexisting rock) deposited at Earth's surface. Typical feature = layering, horizontal bands formed by settling of grains in water (or land)
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Classes of Rocks - Sedimentary Typical texture = compacted or cemented (grains compressed together with or without mineral cement).
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Classes of Rocks - Metamorphic Form when preexisting rock changes (shape or mineral content) due to intense heat and pressure; usually occurs deep below Earth's surface (e.g., during mountain building). Typical texture = foliated (and interlocking), metamorphic banding.
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Rock Cycle Depicts where and how three rock classes form and how they are related to each other
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Rock Cycle Each rock class forms from preexisting rock (constantly recycled), sedimentary rocks form near Earth's surface, metamorphic rocks form at great depths, molten rock occurs at various depths, forming igneous rock when it cools
Essentials of Geology, 4th edition, by Stephen Marshak © 2013, W. W. Norton ! Chapter 3: Patterns in Nature: Minerals!
Rock Cycle Cycle is driven by burial, which sends rock deeper underground and uplift, which brings rock back to surface; Can be interrupted, i.e., doesn’t have to proceed through entire cycle