| A | B |
|---|
| weathering | natural process; atmospheric & environmental agents (wind, rain, temperature changes) disintegrate & decompose rocks |
| mechanical weathering | the process by which rocks break down into smaller pieces by physical means |
| abrasion | the grinding & wearing away of rock surfaces through the mechanical action of other rock or sand particles |
| chemical weathering | the process by which rocks break down as a result of chemical reactions |
| oxidation | reaction that removes 1 or more electrons from a substance-the substance's valence or oxidation state increases |
| hydrolysis | a chemical reaction betweeen water & another substance to form 2 or more new substances |
| carbonation | the conversion of a compound into a carbonate |
| acid precipitation | precipitation (rain, sleet, snow) that contains a high concentration of acids, often because of pollution of the atmosphere |
| differential weathering | process by which softer, less weather resistant rocks wear away at a faster rate than harder, more weather resistant rocks do |
| soil | a loose mixture of rock fragments & organic material that can support the growth of vegetation |
| soil profile | a vertical section of soil that shows the layers of horizons |
| horizon | horizontal layer of soil; distinguished from the layers above & below it; boundary between 2 rock layers |
| humus | dark, organic material formed in soil from the decayed remains of plants & animals |
| erosion | process where materials of Earth's surface are loosened, dissolved, worn away-transported by natural agents |
| sheet erosion | the process by which water flows over a layer of soil & removes the topsoil |
| mass movement | the movement of a large mass of sediment or a section of land down a slope |
| solifluction | the slow, downslope flow of soil saturated with water in areas surrounding glaciers at high elevations |
| creep | the slow downhill movement of weathered rock material |
| landform | a physical feature of Earth's surface |
