| A | B |
|---|
| abrasion | a type of erosion that occurs when windblown sediments strike rocks and sediments, polishing and pitting their surface. |
| alluvial fan | a triangular deposit of sediment that forms when water rushing down a slope loses its energy and slows, depositing its sediment load. |
| barrier island | a temporary sand deposit that parallels the shore but is separated from the mainland by water. |
| chemical weathering | occurs when chemical reactions dissolve the minerals in rocks or change them into different minerals. |
| creep | a type of mass movement in which sediments move downslope very slowly; is common in areas of freezing and thawing, and can cause walls, trees, and fences to lean downhill. |
| deposition | dropping of sediments that occurs when an agent of erosion, such as gravity, a glacier, wind, or water, loses its energy and can no longer carry its load. |
| deflation | a type of erosion that occurs when wind blows over loose sediments, removes small particles, and leaves coarser sediments behind. |
| delta | a triangular deposit of sediment that forms when a stream or a river slows as it empties into an ocean, gulf or lake. |
| drainage basin | land area from which a river or stream collects runoff. |
| erosion | process in which surface materials are worn away and transported from one place to another by agents such as gravity, water, wind, and glaciers. |
| floodplain | a broad, flat valley floor carved by a meandering stream and often covered by water when the stream floods. |
| glaciers | large, moving masses of ice and snow that change large areas of Earth's surface through erosion and deposition. |
| ice wedging | mechanical weathering process that occurs when water freezes in the cracks of rocks and expands, causing the rock to break apart. |
| loess | windblown deposit of tightly packed, fine-grained sediments |
| longshore current | current that runs parallel to the shoreline, is caused by waves colliding with the shore at slight angles, and moves tons of loose sediment. |
| mechanical weathering | physical process that breaks rocks apart without changing their chemical makeup; can be caused by ice wedging, animals, and plant roots. |
| moraine | large ridge of rocks and soil deposited by a glacier when it stops moving forward. |
| oxidation | chemical weathering process that occurs when metallic material is exposed to oxygen and water over time. |
| plucking | process that adds gravel, sand, and boulders to a glacier's bottom and sides as water freezes and thaws, breaking off pieces of surrounding rock. |
| runoff | any rainwater that does not soak into the ground or evaporate but flows over Earth's surface; generally flows into streams and has the ability to erode and carry sediments. |
| soil | mixture of weathered rock, decayed organic matter, mineral fragments, water, and air that can take thousands of years to develop. |
| soil profile | vertical section of soil layers, each of which is a horizon. |
| slump | a type of mass movement that occurs when a mass of material moves down a curved slope. |
| till | mixture of different-sized sediments that is dropped from the base of a retreating glacier and can cover huge areas of land. |
| weathering | mechanical or chemical surface processes that break rocks into smaller and smaller pieces. |
