Lynn S' Fichter

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The Interpretation of Earth History And the Study
of Sedimentary Rocks
Lynn S. Fichter

• Department of Geology/Environmental Science

• E-mail fichtels_at_jmu.edu

• James Madison University

• http//csmres.jmu.edu/geollab/Fichter/Fichter/Fich
  terls.html

• July, 2006

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The Interpretation of Geologic History Requires
Knowledge of the Following
The Interpretation of Sedimentary Rocks Requires
Knowledge of the Following
1. Sedimentary Rocks

• Rock Classification

2. Igneous Rocks
2. Depositional Environments
3. Metamorphic Rocks
3. Sedimentary Structures
4. Origin and History of Life
4. Sedimentary Tectonics
5. Tectonics, including
5. Sedimentary Facies and Time

• Structural geology
• Plate tectonic theory
• Etc.

The core concept is tectonics since nothing in
geology makes sense except in the light of
tectonics
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What is a Depositional Environment?
I am going to the beach
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What is a Depositional Environment?
Tuscarora Sandstone Seneca Rocks, W.Va.
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What is a Depositional Environment?
Oriskany Sandstone Chimney Rock Brocks Gap,
Virginia
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What is a Depositional Environment?
Muav Limestone
Bright Angle Shale
Tapeats Qtz ss
Tapeats Sandstone Grand Canyon, Arizona
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What is a Depositional Environment?
Tapeats Sandstone Grand Canyon, Arizona
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What is a Depositional Environment?
Tapeats Sandstone Grand Canyon, Arizona
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Geologically . . . A depositional environment is
not defined as a thing or a place.
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Depositional environments are defined as
processes . . . By the dissipation of energy
Things fall
Gravitational Energy
Landslides
Solar Energy
Water flows downhill
Biological Energy
Heat causes things to move
Chemical Energy
Drives the winds that makes the waves, and causes
the rain
Which leads to the following concepts
Dip-Fed Systems
- gravity dominates
Strike-Fed Systems
- Solar energy dominates
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Depositional Environments
High Mountain Sourceland
Proximal
Dip Fed
Dip Fed
Strike Fed
Strike Fed
Deep water basin
Distal
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PROXIMAL
Dip Fed
High Mountain Sourceland
Strike Fed
Dip Fed
Strike Fed
Strike Fed
Strike Fed
DISTAL
Deep water basin
http//www.homepage.montana.edu/ueswl/images/thei
linpike.gif
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Depositional Environments
Meandering River
Alluvial Fan
Tidal Flat
Braided River
Delta
Submarine Canyon
Shelf
Beach
Submarine Fan
Lagoon
Barrier Island
Basin
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This summer we have two principles as our mantra
of exploration . . .
Two Principles
1. No rock in accidental.
2. Follow the energy.
What follows is mostly about follow the energy
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Follow the Energy