Earthquakes Flashcards
Define fault scarp
A small step on the ground surface where one side of a fault has moved vertically with respect to the other
Define fault line
The ground surface exposure of a fault
Define a strike
Compass orientation of the line of intersection between the plane of interest and the Earth’s surface
Define a dip
The angle the plane makes with the horizontal surface; it measures steepness
What is a Normal fault
A dip-slip fault where the hanging wall moves down relative to the footwall
What is a reverse fault?
A dip-slip fault where the hanging wall moves up relative to the footwall
What is a thrust fault?
Has the same sense of a slip as a reverse fault, but the fault is at a much gentler angle
What is a strike-slip fault?
A near vertical fracture on which slip occurs parallel to the strike (no up or down motion takes place on these faults)
What is displacement?
The amount of movement across a fault
Define stress
The force applied to an object
Define compressive stress
Normal stress where rock is being pushed
Define tensile stress
Normal stress where rock is being pulled
Define shear stress
Shear moves one part of a material sideways relative to another part
Define strain
Deformation (change in shape) resulting from stress
Define stick
Friction prevents motion
