Wiki Page, B6: World Geography and Civilizations, term 1-1: Changes on the earth's surface

Wiki Page
2013-10-21T10:38:15-06:00

weathering - breakdown of rock at or hearth the earth's surface into smaller and smaller pieces.

mechanical weathering - occurs when rock is actually broken or weakened physically. Most common type of mechanical weathering takes place when water freezes to ice in a crack in the rock.

chemical weathering - alters a rock's chemical makeup by changing the minerals that form the rock or combining them with new chemical elements. An example of chemical weathering is acid rain (chemicals in the polluted air combine with water vapor and fall back to earth as acid rain).

erosion - the movement of weathered materials such as gravel, soil, and sand. The three most common causes of erosion are water, wind, and glaciers.

sediment - small particles of soil, sand, and gravel.

loess - windblown deposits of mineral-rich dust and silt.

glaciers - huge, slow-moving sheets of ice.

moraines - when glaciers melted and receded in some places they left behind ridge like piles of rocks and debris.