In the context of folds, this is the imaginary plane that contains the hinge lines of successive layers in the fold; it is the surface that divides a fold into its two separate limbs.
A long-lived block of durable continental crust commonly found in the stable interior of a continent.
A change in the shape, position, or orientation of a material, by bending, breaking, or flowing.
The angle at which a layer tilts, relative to horizontal; the angle is measured in an imaginary vertical plane that trends perpendicular to the strike.
The bending and flowing of a material (without cracking and breaking) subjected to stress.
A small step on the ground surface where one side of a fault has moved vertically with respect to the other.
A bend or wrinkle of rock layers or foliation; folds form as a consequence of ductile deformation.
Layering formed as a consequence of the alignment of mineral grains, or of compositional banding in a metamorphic rock.
global positioning system (GPS)
A satellite system people can use to measure rates of movement of the Earth's crust relative to one another, or simply to locate their position on the Earth's surface.
The condition that exists when the buoyancy force pushing lithosphere up equals the gravitational force pulling lithosphere down.
A fold in the land surface whose shape resembles that of a carpet draped over a stair step.
The process in which mountains begin to collapse under their own weight and spread out laterally.
Force per unit area, or the รpushร acting on a material in cases where the push is the same in all directions.
The change in shape of an object in response to deformation (i.e., as a result of the application of a stress).
The push, pull, or shear that a material feels when subjected to a force; formally, the force applied per unit area over which the force acts.
A fault in which one block slides horizontally past another (and therefore parallel to the strike line), so there is no relative vertical motion.
A gently dipping reverse fault; the hanging-wall block moves up the slope of the fault.