Fracturing and Faulting Flashcards
Continuous curve in rock layers
Folds
What is the cause of a fold?
Ductile Deformation
Downward sag
Syncline ^U^
Upward arch
Anticline ^n^
Straight sides of a fold
Limb
Curved center of fold
Axis or nose
What causes most folds?
Almost always Compressional Stress
Fold style in which both sides match
Symmetrical fold
Fold style where one side is steeper
Asymmetrical fold
Fold style where one side is upside down
Overturned fold
Both sides fall
Recumbent fold
As folds erode, the strongest rock layers make the _____ topographic features
Highest
Does fold shape = Topography?
NO
Exposed fault surface
Scarp
Fault black you could walk on
Footwall
What can move either up or down?
Footwall
Hanging-wall
Fault block that hangs over your head
Hanging-wall
hanging-wall block slides down the fault plane
Normal Faults
Fault movement creates a gap stretching the rocks
Normal Faults
The hanging wall block slides up the fault
Reverse Faults
Movement creates an overlap bunching up the rocks
Reverse Faults
Compressional stress (subduction/collision)
Reverse Faults
The hanging wall block slides up a very flat fault plant
Thrust Faults
This creates a enormous overlap (easier to go further)
Thrust Faults
= Most mountains (subduction/collision)
Thrust Faults
Motion is all horizontal, no up or down. Each side of the fault moves sideways
Strike Slip Faults
Shear stress (transform zones)
Strike Slip Faults
Rocks can be moved 100’s to 1000’s of miles apart
Strike Slip Faults
Extentional stress (rifting/spreading)
Normal Faults
