| A | B |
|---|
| Deformation | change in shape or volume of a rock |
| Stress | rocks are crumbled into folds or fractures as a result of this |
| Strain | the deformation caused by stress |
| Compression | stress resulting when rocks are squeezed by external forces directed toward oneanother |
| Tension | type of stress in which forces act in opp directions but along same lin, tend to stretch an obj |
| Shear Stress | forces act parallel to one another, but in opp directions resulting in deformation by displacement along closely spaced planes |
| Elastic Strain | type of deformation in which the material returns to its original shape when stress is relaxed |
| Plastic Strain | type of deformation when they yield by folding or the behave like brittle solids and fracture |
| Strike | the compass direction of a line formed by the intersection of an inclined plane w/a horizontal line |
| Dip | measure of an inclined plane's max inclination from horizontal and is measured at right angles to the strike direction |
| Monoclines | bends or flexures |
| Anticlines | up-arched folds; beds dipping away fold axis; older beds in middle in map view |
| Synclines | down-arched folds; beds dip toward the fold axis in cross section, younger beds in middle in map view |
| Plunging Fold | fold axis dips into subsurface, results is chevron patterns in map view |
| Basins | beds dip toward the center of the basin, younger beds in mid in map view, a doubly plunging syncline |
| Dome | beds dip away from center of dome, older beds in middle in map view, a doubly plunging anticline |
| Joints | fractures w/ no displacement often associated w/folding |
| Fault | fractures along which movement has taken place |
| Footwall | lies below the fault plane |
| Hanging wall | lies above the fault plane |
| Dip-Slip Fault | formed by tensional or compressive stress |
| Normal Fault | due to tension hanging wall moves down |
| Reverse Fault | caused by compression, hanging wall moves up |
| Thrust | low-angle reverse fault |
| Stirike-Slip Fault | formed by shear forces; are right lateral or left lateral |
| Oblique-Slip Fault | both dip and strike movement |
| Terranes | differ completely in their fossil content, structural trends, and paleomagnetic properties from rocks of the surrounding mntn system |
| Principle of Isostasy | Crust is floating in equilibrium on the denser mantle below |
| Isostatic rebound | occurs when loading or unloading of the crust occurs through sedimentation, glacial activity, or erosion |
