EOSC 110 Chapter Notes - Chapter 15: Convergent Boundary, Shear Stress, Compressive Stress
Document Summary
Strain: the change in shape or size(volume) in response to stress. Compressive stress: rocks being shortened or flattened (convergent plate boundaries where rocks have been pushed or shoved together) Tensional stress: caused by forces pulling away from one another in opposite directions. Stretching or extension of material (divergent boundaries, rocks are weak and when they are pulled apart, fractures and faults are common structures. Shear stress: stresses act parallel to a plane. (actively moving faults) Depends on amount and rate of stress applied, type of rock, temperature and pressure. If a deformed material recovers its shape its behavior is elastic. Once the stress exceeds the elastic limit the rock will deform in a permanent. Ductile behaviour bends while under stress and does not return to its original way shape. Brittle behaviour will fracture at stresses higher than its elastic limit (near the surface of the earth, where temperature and pressure are low).
