Question 1

In your own words, describe the difference between weathering, erosion, and mass wasting.

Accepted Answer

Weathering generally restricted to material breakdown in place. The physical and chemical changes that occur in rocks happens at the interface of the Earth's hydrosphere and atmosphere. Mass Wasting is when material falls under influence of gravity with little or no transporting agent. And erosion refers to processes that move material to another site under the influence of transporting agents such as water, ice, and/or wind.

Question 2

Rounding of angular edges of rock outcropping and formation of insitu, spherical boulders are both indications of ________.

Accepted Answer

chemical weather and associated spheroidal weathering

Question 3

All of the following are factors that affect rates of weathering except for ________.a) rock characteristicsb) surface areac) climate d) geologic age of earth materials

Accepted Answer

d) geologic age of earth materials

Question 4

Which one of the following statements concerning mechanical weathering is NOT true?a) reduces grain sizes of rock particlesb) allows for faster rates of chemical weatheringc) is important in the formation of talus slopes d) involves a major change in the mineral composition of the weathered material

Accepted Answer

d) involves a major change in the mineral composition of the weathered material

Question 5

What two factors speed up rates of chemical reaction and weathering in rocks and soils?a) low temperatures; very dryb) low temperatures; very moistc) high temperatures; very dryd) warm temperatures; very moist

Accepted Answer

d) warm temperatures; very moist

Question 6

One important relationship between chemical and mechanical weathering is ________.

Accepted Answer

mechanical weathering can produce smaller pieces of rock that have more surface area for chemical weathering to work on.

Question 7

Limestone and marble weather faster than granite because ________.

Accepted Answer

limestone and marble can be dissolved by weak acids in rain

Question 8

A geologist is looking at deposits along a river below a large volcano. She finds large boulders mixed with sand and mud, and all of the material is comprised of volcanic rocks, particularly the mud which is volcanic ash. She quickly realizes these deposits represent an ancient ________.

Accepted Answer

lahar

Question 9

Climate change and human activity like overgrazing of grasslands is leading to large areas subject to desertification where native grass cover dies out during drought periods, exposing soil to erosion. What is potentially the greatest initial soil erosion potential during this type of an event?

Accepted Answer

loss of topsoil by wind erosion on a large scale

Question 10

Which of the following is most resistant to both chemical and physical weathering?a) clay mineralsb) quartzc) a granited) a limestone

Accepted Answer

b) quartz

Question 11

Which one of the following statements concerning mechanical weathering is nottrue?a) reduces grain sizes of rock particlesb) allows for faster rates of chemical weatheringc) is important in the formation of talus slopesd) involves a major change in the mineral composition of the weathered material

Accepted Answer

d) involves a major change in the mineral composition of the weathered material

Question 12

Which of the following statements concerning mudflows is NOT true?a) Mudflows may be caused by heavy rains or melting snow.b) In hilly areas, mudflows move down the canyons and stream valleys.c) Mudflows deposit talus slopes.d) Mudflows can move and carry very large boulders and other coarse debris.

Accepted Answer

c) Mudflows deposit talus slopes.

Question 13

The word topsoil is commonly used, but not always correctly. The proper definition is ________.a) the A, E and B horizonsb) the dark, organic rich layers of O and Ac) the entire soil down to the base of the C horizond) only the O horizon

Accepted Answer

b) the dark, organic rich layers of O and A

Question 14

How might a forest fire influence mass wasting?

Accepted Answer

Large scale mass wasting events frequently follow forest fires because their were sudden changes made to the vegetative cover. The vegetative cover refers to trees, bunchgrasses and grasslands, legumes, and shrubs with an expected life span of at least 5 years. After the vegetative cover is destroyed by a forest fire, it leaves the hillsides bare which causes normal rainstorms to saturate the ground and cause mudslides that do tremendous damage.

Question 15

Deforestation of rain forests exposes tropical soils that are famous for their low fertility, despite the fact that they had previously hosted a lush tropical forest. Which soil type would describe these soils?

Accepted Answer

Oxisols&mdash;Soils that occur on old land surfaces unless parent materials were strongly weathered before they were deposited. Rich in iron and aluminum oxides, Oxisols are heavily leached, hence are poor soils for agricultural activity

Question 16

How does deforestation by fire or human activity contribute to mass wasting?a) It allows excess rainfall runoff to erode the landscape, triggering mass wasting.b) It kills tree roots that help hold the slopes in place, allowing mass movement.c) It allows the wind to blow across the slopes, imparting a stress that triggers landslides.d) It allows farming activity that exposes soil to erosion and mass wasting.

Accepted Answer

b) It kills tree roots that help hold the slopes in place, allowing mass movement.

Question 17

Mass wasting, a process that often occurs between weathering and erosion, involves ________.

Accepted Answer

the transport of material due to gravity

Question 18

In the Rocky Mountain region of the United States, north-facing slopes (downhill direction is toward the north) are typically moister and more heavily forested than south-facing slopes. Why?

Accepted Answer

North-facing slopes receive about the same amount of precipitation as south-facing slopes; less moisture evaporates from north-facing slopes.

Question 19

From the land surface downward to the unweathered bedrock, which of the following is the correct order of the different soil horizons?

Accepted Answer

O, A, E, B, C, bedrock

Question 20

Which one of the following statements best describes erosion?a) disintegration and decomposition of rocks and minerals at the surfaceb) movement of weathered rock and regolith toward the base of a slopec) the process by which weathered rock and mineral particles are removed from one area and transported elsewhered) the combined processes of leaching, eluviation, and mass wasting

Accepted Answer

c) the process by which weathered rock and mineral particles are removed from one area and transported elsewhere

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