Question

unit 2 study guide: surface processes on earth

1. what role does water play in chemical weathering?
2. how does groundwater contribute to the breakdown of rocks?
3. what is one major effect of surface water on earths surface?
4. define physical weathering.
5. how can temperature changes lead to physical weathering?
6. what is a common result of chemical weathering?
7. give an example of physical weathering.
8. what is the term for the rapid movement of rock and soil down a slope?
9. what type of mass wasting occurs when saturated soil becomes unstable?
10. name a type of mass wasting that happens slowly over time.
11. what is one natural trigger for sudden mass wasting?
12. what is a result of gradual mass wasting over time?
13. how do heavy rains affect slope stability?
14. what type of sudden mass wasting involves falling rocks?

Explanation:

1. Water can dissolve minerals in rocks and participate in chemical reactions like oxidation and carbonation in chemical weathering.
2. Groundwater seeps into rocks, can dissolve minerals and cause expansion - contraction cycles as it freezes and thaws, contributing to rock breakdown.
3. Surface water can erode the Earth's surface, creating valleys, canyons, and river deltas.
4. Physical weathering is the breakdown of rocks into smaller pieces without changing their chemical composition, often by mechanical forces.
5. Temperature changes cause rocks to expand and contract. Repeated cycles can lead to cracks and fragmentation.
6. A common result of chemical weathering is the formation of new minerals, such as clay minerals from the weathering of feldspar.
7. An example of physical weathering is frost - wedging, where water freezes in rock cracks and expands, breaking the rock.
8. The term for the rapid movement of rock and soil down a slope is a landslide.
9. When saturated soil becomes unstable, a mudflow occurs.
10. Creep is a type of mass wasting that happens slowly over time, as soil and rock gradually move down a slope.
11. An earthquake can be a natural trigger for sudden mass wasting, shaking loose rocks and soil.
12. A result of gradual mass wasting over time is the reshaping of the landscape, such as the formation of gentle slopes.
13. Heavy rains can increase the weight of soil on slopes and reduce friction, making slopes more unstable.
14. Rockfall is a type of sudden mass wasting that involves falling rocks.

Answer:

1. Water participates in chemical reactions like dissolution, oxidation, and carbonation.
2. Seeps in, dissolves minerals and causes expansion - contraction.
3. Erosion creating valleys, canyons, deltas.
4. Breakdown without chemical change by mechanical forces.
5. Expansion - contraction from temperature cycles causes cracking.
6. Formation of new minerals like clay.
7. Frost - wedging.
8. Landslide.
9. Mudflow.
10. Creep.
11. Earthquake.
12. Landscape reshaping (gentle slopes).
13. Make slopes more unstable by adding weight and reducing friction.
14. Rockfall.