Geologic Structures

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Lecture 18 Geologic Structures
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Lecture Outline
I Stress and Strain II Geologic Mapping A) Plan
View B) Cross Section III Folds A)
Geometry B) Interpretation IV Fractures A) Join
ts B) Faults i. Dip-Slip Faults ii. Strike-
Slip Faults V Conclusions
Lecture 18 i
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Tectonic Settings
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Types of Stress
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Stress and Strain
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Stress and Strain Types of Deformation

• Brittle

• Ductile (Plastic)

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Stress and Strain Types of Deformation -
Controlling Factors

• Temperature
• Pressure
• Strain Rate
• Rock Type

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Tectonics, Stress and Strain
Ductile
Brittle
Convergent Plate Boundary
Divergent Plate Boundary
Transform Plate Boundary
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Strike and Dip
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Strike and Dip
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Geologic Mapping
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Folds
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Folds
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A Series of Folds
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Folds
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Folds
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Plunging Folds
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Domes and Basins
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Structural Dome
Sinclair Dome, Wyoming
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Fractures

• Joints
• Faults

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Fault Types

• Dip-Slip

• Normal
• Reverse
• Thrust

• Strike-Slip

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Faults Hanging Walls and Foot Walls
Hanging Wall
Foot Wall
Foot Wall
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FaultsNormal
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FaultsNormal - Horst and Graben
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FaultsNormal - Horst and Graben
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FaultsReverse
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FaultsThrust
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FaultsStrike-Slip
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FaultsStrike-Slip
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FaultsOblique-Slip