Erosion Study Guide - answers

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Study Guide
Erosion and water
This study guide is designed to help you prepare for the next test.
Students who take the time to answer each of the following questions should do well.
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What is weathering?
The process that breaks down and changes rock at Earth’s surface. (p. 334)
What is erosion?
The process of moving weathered material from one place to another. (p. 342)
What is deposition?
The process where sediment is laid down in a new location. (p. 342)
Most erosion is caused by ______________________.
Water, specifically running water (notes)
How does running water change the surface of the earth?
Rivers pick up sediment and carry it to a new location. Faster water causes more erosion than slower
water. Deposits made by rivers include oxbow lakes, alluvial fans and deltas. (p. 345-346)
What is a meander?
A curve in a river (p. 345)
Which part of a meander is eroded? Where does deposition occur?
Erosion occurs along the outside of the curve where water moves faster. Deposition occurs on the
inside of the curve where the water moves slower. (p. 345)
Describe oxbow lakes, deltas and alluvial fans.
Oxbow lake: Crescent shaped lake next to a river formed when a meander gets cut off.
Delta: Triangular deposit of sediment at the mouth of a river where it enters a large body of water.
Alluvial Fan: Triangular deposit of sediment at the base of a canyon. (p. 346)
What is a flood? What is the floodplain?
A flood occurs when the water level in a river overflows its banks. The floodplain is the large, flat
valley through which a river flows. (P. 348)
How can we protect an area from flooding?
Dams and levees are used to protect an area from flooding (p. 348)
How do waves change the surface of the Earth?
Waves crash into the shore creating features such as cliffs, caves, sea stacks, and sea arches. (p.
349-350)
What are some features of erosion at the beach? Describe.
Cliff: caused by cutting action of waves
Cave: cave at bottom of sea cliff
Sea Stack: column of rock
Sea Arch: a hole carved out. (p. 349 and notes)
What is longshore current?
Movement of the water that moves large amounts of sediment along the coast. Waves hit the coast
from an angle. (p. 350)
How can we protect beaches from erosion? What is a groin?
Retaining walls, harbor channels and groins. A groin traps sand that would typically be moved along
the coast by longshore current. It’s like a dam that sticks out at a right angle to the shore. (p. 350)
What is a glacier?
A large mass of ice and snow. (p. 350)
About how fast do glaciers move?
Approximately 2.5cm/day. (p. 350)
Differentiate between valley and continental glaciers. Where do we find continental glaciers?
Valley glaciers form in existing stream valleys high in the mountains. Continental glaciers cover
entire areas of land. Greenland and Antarctica are continental glaciers. (p. 350)
18. How do glaciers shape the land?
Trapped rocks and boulders scrape the ground as the glaciers move. Striations. Till builds up at the
front and sides of glaciers. Outwash also deposited. (p. 351)
19. What deposits are made by glaciers? Describe.
Till: sediment deposited by a glacier. Sometimes in ridges called moraines.
Outwash: rivers formed by melting glaciers deposit sediment. (p. 351)
20. What is mass wasting?
A form of erosion caused by gravity. (p. 343)
21. Describe 5 types of mass wasting.
Landslide: rapid, gravity- caused events that move soil, loose rock and boulders
Mudslide: mixtures of soaked soil and rock
Rock fall: loosened rock falling from steep cliffs
Slump: a block of rock and overlaying soil slide down as one large mass
Creep: sediment moves slowly down hill. (p. 343)
22. How does climate effect mass wasting?
Regions with more rainfall are more likely to experience mass wasting. (p. 344)
23. Know that rivers carve V-shaped valleys and glaciers carve U-shaped valleys.
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