Erosion

1. Chemical weathering occurs most rapidly in climates which are

moist and warm
moist and cold
dry and cold
dry and warm

2. Which material could best be carried in solution by a stream?

Clay
Salt
Silt
Sand

3. Rounded-bottom valleys with almost vertical sides, small ridges made of unsorted sediments, and exposed bedrock with small, parallel groves were almost certainly formed by

extensive glaciation
volcanoes and lava flows
earthquakes and associated faulting
flooding followed by periods of wind erosion

4. The diagram represents blocks of limestone. Which block will weather at the greatest rate?



1
2
3
4

5. What conditions must occur in order for rocks to weather?

The rocks must be composed of silicate materials
The rocks must be moved by erosion
The rocks must be deeply buried in the earth
The rocks must be exposed to air or water

6. At high elevations in New York State, which is the most common form of physical weathering?

Abrasion of rocks by the wind
Dissolving of minerals into solution
Alternate freezing and melting of water
Oxidation of minerals by exposure to atmospheric oxygen

7. Very small solid sediments (colloids) are carried by a stream

by floatation
in suspension
in solution
by rolling

8. The most important result of the weathering of rock as far as living things are concerned is the

leaching of minerals from rocks
release of oxygen by frost action
formation of soil
erosion which results

9. At which locations will the rate of erosion be greatest?



A and C
B and C
A and D
E and F

10. A sample of a sedimentary deposit is found to contain coarse rock fragments at the bottom and fine particles at the top. The deposition most likely occurred as a result of

dropping directly from a glacier
a decrease in the velocity of a stream
an avalanche on a mountainside
dropping of weathered rock fragments from a cliff

11. Directly or indirectly, the cause of most erosion is

water
wind
the earth's rotation
gravity

12. Which rock material in the diagram is most resistant to weathering?



A
B
C
D

13. Why does one gram of finely ground salt dissolve more rapidly in water than an equal mass of coarsely ground salt?

Grinding changes the chemical composition of the salt
Finely ground salt is less dense than coarsely ground salt
More surface area is exposed in finely ground salt
The solubility of the salt is proportional to the mass of the salt

14. Which is the best example of physical weathering?

The transportation of sediments by a stream
The cracking of rock caused by the freezing and thawing of water
The effect of acid rainwater on limestone
The formation of a sandbar along the side of a stream

15. As the kinetic energy of a stream increases, the size of the particles that can be transported by that stream

increases
decreases
remains the same

16. The two most important factors responsible for the velocity of a stream are it's slope and

direction
type of underlying rock
volume of water
water temperature

17. Which graph correctly shows the relationship between stream discharge and stream velocity?



1
2
3
4

18. What is the main difference between chemical and physical weathering?

Chemical weathering alters mineral composition. Physical processes don't
Chemical weathering increases surface area. Physical processes do not
Physical weathering alters mineral composition. Chemical processes don't
Physical weathering increases surface area. Chemical processes do not

19. Which agent of erosion probably contributes most to the general wearing down of the earth's surface?

Glaciers
Running water
Ocean waves
Wind

20. Which rock has probably been exposed to the longest period of stream abrasion?



1
2
3
4

21. At which location would the smallest particles be deposited?



B
C
E
F

22. Which rock material was probably transported to its present location by a glacier?

Rounded sand grains found in a river delta
Rounded grains found in a sand dune
Grains found in a layer of stratified soil
Unsorted, loose gravel found in hills

23. The rate at which particles are deposited by a stream is least effected by

The size and shape of the particles
The velocity of the stream
The stream's elevation above sea level
The density of the particles

24. Which pair of temperature and rainfall conditions would tend to promote the most intense weathering of a rock

Low temperature and low rainfall
Low temperature and high rainfall
High temperature and low rainfall
High temperature and high rainfall

25. Large caves in limestone rock are produced when carbon dioxide dissolves in water to produce

Quartz
Hydrates
Calcium carbonate
Carbonic acid

26. Diagram 1 shows the water velocity at the surface of a stream. Diagram 2 shows the water velocity at different depths in the same stream. At which location is the water velocity greatest?



At the surface in the middle of the stream
At the surface near the bottom of the stream
Along the sides at the surface of the stream
Along the sides near the bottom of the stream

27. According to the Earth Science Reference Tables, particles with a diameter of 0.002 cm. should be classified as

Pebbles
Sand
Silt
Clay

28. According to the Earth Science Reference Tables, a stream velocity of 100 cm./sec is sufficient to transport

Cobbles, pebbles and sand
Boulders, cobbles and pebbles
Cobbles, pebbles, sand and silt
Pebbles, sand, silt and clay

29. According to the Earth Science Reference Tables, what is the minimum stream velocity needed to maintain the movement of boulders (diameter 25.6 cm.)?

100 cm/sec
200 cm/sec
300 cm/sec
400 cm/sec

30. Wide, U-shaped valleys are most closely associated with erosion by

Rivers
Glaciers
Wind
Gravity

31. Which graph correctly shows the relationship between the months of the year and the rate of chemical weathering for a location in New York State?



1
2
3
4

32. A hilly region on Long Island is composed of unconsolidated and unsorted sediments. Which erosional agent was probably most influential in forming this landscape?

Wave action
Streams
Glaciers
Wind

33. If a sediment is only partly rounded and has large scratches, it was most likely transported by

Wind
Streams
Gravity
Glaciers

34. A farmer who leaves the soil barren of vegetation will probably increase the amount of

Infiltration
Physical weathering
Erosion
Chemical weathering

35. Which of these sediments would you expect to find in the greatest quantity far out into the ocean because of suspension of sediments?

Sand
Pebbles
Colloids
Silt

36. The sediment depicted in the diagram was most probably deposited by



Glaciers
A stream
Wind
Waves

37. Angular rock fragments at the bottom of a cliff were probably transported by

Wind
Streams
Gravity
Glaciers

38. Large solid sediments such as pebbles are most often carried by a stream

In solution
By rolling
In suspension
By floating

39. The diagram represents a section of sediment ranging from large pebbles on the bottom to fine sand at the top. This sediment was most likely deposited by



A glacier
A stream
Wind
Particles falling directly from a cliff

40. Soil forms layers called

Beds
Stratifications
Horizons
Zones

41. The chemical composition of a residual soil in a certain area is determined by the

Method by which the soil was transported to the area.
Slope of the land and the particle size of the soil
Length of time since the last crustal movement in the area occurred.
Minerals in the bedrock beneath the soil and the climate of the area

42. As the grain size of suspended material increases, the rate of settling

Increases
Decreases
Remains the same

43. The velocity of a stream is 100 cm/sec. According to the Earth Science Reference Tables, what is the largest diameter particle that can be transported by this stream?

1.0 cm
0.1 cm
0.01 cm
0.001 cm

44. Which is indicated by a deeper residual soil?

Resistant bedrock
A large amount of glaciation
A long period of weathering
A youthful stage of erosion

45. Which rock layer is most resistant to weathering?



A
B
C
D

46. What would happen to the lansdcape pictured in the diagram if the climate became more humid?



The elevation of the region would increase
The landscape features would become more rounded
Stream channels would fill with sediment
U-shaped valleys would form

47. In which zone would particles with a size range of 0.05 cm to 0.10 cm be found?



Zone A
Zone B
Zone C
Zone D

48. If the stream discharge between points X and Y increased, the most likely result would be



A decrease in the amount of erosion
A decrease in the average stream velocity
An increase in the deposition of sediments between X and Y
An increase in the particle size of sediments entering the ocean

49. If point X were uplifted, the potential energy of the stream at point X would



Increase
Decrease
Remain the same

50. The diagram represents a vertical cross section of sediments deposited by a stream. Which statement best explains the mixture of sediments?



The velocity of the stream continually decreased.
The stream discharge continuall decreased.
The particles have different densities.
Smaller particles settle more slowly than larger particles.

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