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Faults and Faulting
Faults and Faulting
Regional Strain
Types of Fault and the Principal Stresses
Fault Rocks
• Gouge: non-cohesive, fine grained• Breccia: coarse angular fragments• Cataclasite: cohesive fragments• Fault Melt (pseudotachylite):
– due to friction• Mylonite: ductile-brittle fault zone
Fault scarp after an earthquake- Nevada
Fault Striations- Slickenlines
Fault zone breccia
in QuartziteBrooks Range,
AK
Hydrothermal Fault BrecciaHydrothermal Fault Breccia
Fault Melt
Fault Melt
Mylonites
Evolution of an ActiveMountain
Front
New Mountains-Active Fault –Basin and Range Province
Slot Canyon, Faulted Alluvial Fan- Death Valley
Some Faults are Almost flat
Faults in Reflection Seismic Data- Hope Basin, AK
Interpreted Seismic Data
3 km
0
The longer a fault, the more displacement
it has
Faults Symbols in Map View
Normal Faults
Thrust Faults
Decorations are on the hanging wall
Fault on a Geological Map
Map View of FaultsSlip vs. Separation
Separation : 2DIf layers are tilted it may be deceiving
These are two dipping dikes that are faulted. What kind of fault is this?
