| A | B |
|---|
| erosion | Movement of weathered materials from one location to another by water, wind, glaciers, and gravity |
| topography | change in elevation of the crust |
| isostacy | condition of equilibrium that describes the displacement of Earth's mantle by Earth's continental and oceanic crusts |
| root | thickened areas of continental crust that extend into the mantle |
| isostatic rebound | slow process of Earth's crust rising as the result of the removal of mass from the crust |
| mode | the number or numbers that occurs most often in a set of data |
| continental drift | Wegener's hypothesis that Earth's continents were joined as a single landmass, called Pangaea, that broke apart about 200 million years ago and slowly moved to their present positions |
| orogeny | cycle of processes that form all mountain ranges |
| compressive forces | squeezing forces that cause intense deformation, such as faulting, metamorphism, and igneous intrusions |
| island arc | series of volcanic peaks created by magma that is forced upward |
| divergent boundary | place where two of Earth's tectonic plates are moving apart; usually found on the seafloor |
| uplifted mountain | mountains formed when large regions of Earth have been slowly forced upward as a unit |
| plateau | a relatively flat uplifted region |
| fault-block mountain | mountains formed when large pieces of crust are tilted, uplifted, or dropped downward between large faults |
| dynamic | relating to an object in motion; relating to or tending toward change |
