GEOL 101 Lecture Notes - Lecture 10: Shear Stress
Document Summary
Deformation: term applied to all changes in the size, shape, orientation, or position of a rock mass. Stress: amount of force per unit area: under stress, rocks can fold, flow, or fracture. Compression stress: stress that shortens a rock body (pushing together) Tensional stress: stress that lengthens a rock body (pulling apart) Shear stress: stress that causes layers within a rock body to slip past one another (moving past each other) Strain: change in shape of a rock body due to stress. Temperature and pressure: at low temperature and pressures, rocks tend to undergo brittle deformation, while at higher temperatures and pressures they tend to undergo ductile deformation. Mapping geologic structures: strike: the compass direction of the line produced by the intersection of a layer with the horizontal surface, dip: the inclination (angle) of the surface measured perpendicular to strike, monoclines: only 1 incline (slope)
