Medium - Short Answer

1. What factors, other than magnitude, determine whether an earthquake will cause lots of damage or kill many people?
2. Describe how the Earth's temperature has fluctuated over the past 65 million years. Are we in a warming or cooling period now?
3. What factors led to America's dust bowl of the 1930s?
4. Where are the principle deserts in the United States? Why are they where they are?
5. When rocks are stressed, they forces can be compressional (squeezing together), tensional (pulling apart), or shear (sliding past). What are the possible results when portions of the Earth's crust are compressed?

Multiple Choice

1) In geology, the term "stress" refers to:
(a) stretching of a rock unit
(b) compression of a rock unit
(c) any deformation of a rock unit
(d) forces that might cause deformation of a rock unit

2) The type of stress that normally occurs at converging plate boundaries is:
(a) compression
(b) tension
(c) strain
(d) shearing

3) Elastic deformation may occur when rocks are subject to:
(a) compressive stress.
(b) tensional stress.
(c) shearing stress.
(d) any type of stress.

4) When a rock undergoes sufficient stress that it cannot return to its original shape after the stress is removed, it is said to have reached its:
(a) plastic limit.
(b) stress limit.
(c) elastic limit.
(d) strain limit.

5) Rocks subjected to relatively high temperatures are more likely to:
(a) deform plastically rather than elastically.
(b) undergo brittle failure rather than plastic deformation.
(c) deform elastically rather than undergo brittle failure.
(d) deform elastically rather than plastically.

6) Mapping the strike and dip of all the rock units in a region is important because:
(a) it shows the location, elevation, and slope gradient of all the hills and valley.
(b) it delineates the three-dimensional subsurface form of rock.
(c) it correlates the locations of all the outcroppings of rocks.
(d) it establishes the points at which stress was applied to each of the rock units.

7) A region exhibiting symmetrical or open synclines and anticlines is more likely to be located:
(a) near a divergent plate boundary.
(b) near a convergent plate boundary.
(c) near a transform plate boundary.
(d) at the edges of mountain belts in areas that are relatively inactive tectonically.

8) A fold in which the axial plane is horizontal with the surface of the Earth is a(n):
(a) asymmetrical fold.
(b) overturned fold.
(c) recumbent fold.
(d) plunging fold.

9) The most extensive type folding occurs:
(a) during continental collisions.
(b) within subducting plate boundaries.
(c) near divergent or rifting plate boundaries.
(d) within transform fault boundaries.

10) Domes and basins are found most commonly:
(a) near a divergent plate boundary.
(b) near a convergent plate boundary.
(c) near a transform plate boundary.
(d) within a continent, away from any plate boundary.

11) A normal fault occurs as a result of:
(a) tensional stress, and the hanging wall moves down relative to the footwall.
(b) tensional stress, and the hanging wall moves up relative to the footwall.
(c) compressional stress, and the hanging wall moves down relative to the footwall.
(d) compressional stress, and the hanging wall moves up relative to the footwall.

12) A thrust fault is the result of:
(a) tensional stress, and the hanging wall moves down relative to the footwall.
(b) tensional stress, and the hanging wall moves up relative to the footwall.
(c) compressional stress, and the hanging wall moves down relative to the footwall.
(d) compressional stress, and the hanging wall moves up relative to the footwall.

13) Continental shields are:
(a) regions in the interior of a continent that have never undergone orogenesis.
(b) mountains existing along the east or west coasts of a continent that shield the interior of the continent from the impacts of plate collisions.
(c) deeply eroded cores of some of the Earth's earliest mountains, which form flat regions in the interior of a continent.
(d) the bedrock that underlies the entirety of a continent, under both mountains and plains.

14) The term "orogenesis" refers to:
(a) only volcanic mountain building.
(b) only nonvolcanic mountain building.
(c) all types of mountain building.
(d) only mountain building at plate margins.

15) Fault-block mountains are characterized by:
(a) vast upwarped regions.
(b) distinctive reverse or thrust faults.
(c) high-angle normal faults.
(d) trust-faulted and folded marine sediments.

16. the ultimate source of the energy transported by water waves is:
a. ocean currents
b. the gravitational pull of the Moon and Sun
c. solar radiation
d. the rotation of the Earth

17. Constructive interference of waves may have occurred when:
a. waves with similar velocities and periods have become synchronized
b. waves with different velocities and periods have become synchronized
c. waves with similar velocities and periods have become unsynchronized
d. waves with different velocities and periods have become unsynchronized

18. Longshore currents are propelled by:
a. tidal fluctuations
b. the zig-zag motion of swash and backwash
c. wave refraction
d. destructive interference between currents

19. The vertical tidal range would probably be the largest:
a. in a bay or estuary
b. along a straight coastline
c. in a large inland lake
d. on an island in the middle of the ocean

20. The principal mechanism by which waves erode coastlines is:
a. abrasion by the sediment load
b. the force of the water battering the rocks
c. by forcing water and air under high pressure into rock crevices
d. dissolution

21. The movement of sand along a beach face is called:
a. longshore current
b. longshore drift
c. beach drift
d. beach current

22. Which manmade structure lies parallel to the coast and is used to create a quiet, wave-free zone?
a. spit
b. breakwater
c. groin
d. jetty

23. Which manmade structure is built in pairs to extend the banks of a stream beyond the coastline?
a. spit
b. breakwater
c. groin
d. jetty

24. Reef organisms are limited geographically by which of the following factors?
a. their need for a reduction in salinity is provided by dilution from freshwater systems
b. their mode of filter feeding helps them to filter quantities of suspended particles from water
c. their growth near the surface is primarily due to their production of food through photosynthesis
d. their warm-water requirements tend to limit their growth to latitudes between 30 degrees north to 25 degrees south

25. Erosional features such as sea stacks and wave-cut benches are commonly associated with:
a. transform fault boundaries
b. older, passive continental margins
c. recently rifted divergent plate boundaries
d. coasts lined with barrier reefs

26. A coastline dominated by narrow beaches caused by extensive river damming exists along with North American coastline?
a. the West Coast from Alaska to northern California
b. the coast of southern California
c. the East Coast north of New York City
d. the East Coast south of New York City

27. During the last period of maximum glacial expansion, sea level was approximately:
a. 140 meters lower than it is today
b. 70 meters higher than it is today
c. at the same level as it is today
d. 70 meters lower than it is today

28. Which of the following statements about deserts is true?
a. desert landscapes consist mostly of sand
b. deserts account for less than 10% of the Earth's surface land
c. desert climates are always hot and dry
d. every continent on Earth contains at least one extensive dry region

29. Warm deserts that result from atmospheric convection cells are:
a. subtropical deserts
b. rain shadow deserts
c. continental interior deserts
d. deserts near cold ocean currents

30. Polar deserts are considered deserts because:
a. they lack vegetation
b. they lack appreciable precipitation
c. the temperatures remain below freezing year-round
d. they receive little solar radiation

31. The primary sculptor of desert landforms is:
a. erosion by raindrop impacts during heavy precipitation
b. erosion and deposition by streams
c. deposition by wind
d. erosion and deposition by wind

32. deflation is:
a. a form of wind deposition
b. a form of wind erosion
c. a phenomena producing a thin, ground-level layer of no wind
d. the cause of wind in a desert

33. Dust sediment in the wind's suspended load:
a. travels in a narrow layer of dead space along the surface of the ground
b. travels at about the same height and distance as the bed load
c. travels at about twice the height and distance of the bed load
d. can travel in the upper atmosphere for a distance of thousands of kilometers

34. The direction of a paleowind can be determined from sandstone if:
a. the sand has been well sorted
b. beds are inclined at the angle of repose for dry sand
c. polished and pitted sand grains can be found
d. two consecutive dunes can be found

35. The time required for fresh snow to become glacial ice in snowy climates is on the order of:
a. a few weeks
b. a few years
c. a few decades
d. thousands of years

36. Glaciers are classified by:
a. their rate of growth
b. their degree of confinement
c. their size
d. the rate at which their ice flows

37. Glacial surges are caused by:
a. an accumulation of water at the base of the glacier
b. rapid internal deformation of the ice
c. a large buildup of snow in the zone of accumulation
d. the weight of sediment trapped within the glacier

38. Observing a roche moutonnee can aid in the determination of the direction of glacial flow because:
a. its symmetrical sides are parallel to glacial flow
b. the down-glacial side is a gentle hump-backed slope
c. the down-glacier side is the most heavily quarried
d. the up-glacier side is steep and jagged

39. The term "glacial drift" applies to:
a. all glacial deposits, collectively
b. glacial deposits of very fine particles that eventually become wind-blown
c. glacial deposits that are carried by meltwater to nearby streams
d. the redistribution of glacial deposits by consecutive advances

40. Till appears different from outwash in that:
a. till contains only smaller particles while outwash contains both small and large rock fragments
b. till is darker in color than outwash
c. till is better sorted and stratified than outwash
d. till is less sorted and stratified than outwash

41. A medial moraine forms:
a. along the sides of a glacier
b. where two valley glaciers merge
c. where a glacier terminus advances beyond a recessional moraine
d. beneath a glacier in a sinuous ridge

42. The principal effect of Milankovitch's astronomical cycles is that:
a. when the cycles are opposed, wintertime radiation increases, causing increased precipitation
b. when the cycles are opposed, solar radiation is at a minimum
c. when the cycles coincide, winters are much more severe
d. when they cycles coincide, summertime radiation is reduced

43. The Earth's earliest known ice age occurred about:
a. 4.6 billion years ago, when the Earth was first formed
b. 2.2 billion years ago, during the Precambrian Ear
c. 66 million years ago, at the end of the age of dinosaurs
d. 2 million years ago, at the beginning of the Pleistocene Epoch

44. The "Little Ice Age":
a. was a period of cooler global temperatures from about 1300 to 1850 A.D. and included glacial expansion in mid-latitude mountain ranges
b. was the last major Pleistocene episode of glaciation, and ended about 10,000 years ago
c. refers to the present Quaternary ice age, which, in geologic terms, has been shorter than many of the Earth's earlier ice ages
d. was the Earth's first known ice age, and occurred during the Precambrian Era

45. Most earthquakes are caused by:
a. magma moving forcefully through underground caverns
b. the release of accumulated strain energy in rocks undergoing plastic deformation
c. the release of accumulated strain energy in rocks undergoing elastic deformation
d. excess lithostatic pressure on rocks buried deep within the earth

46. Earthquake waves that alternately cause rocks to compress and dilate are:
a. P waves
b. S waves
c. side-to-side surface waves
d. rolling surface waves

47. Earthquakes measuring 5 and 7 on the Richter scale differ in wave amplitude by:
a. 2 times
b. 10 times
c. 100 times
d. 7/5 = 1.4 times

48. The magnitude of most of the Earth's earthquakes is from ____ on the Richter scale.
a. 1.0 to 2.0
b. 2.0 to 3.0
c. 3.0 to 3.9
d. 4.0 to 4.9

49. Japan is the site of about 15% of the Earth's seismic energy release because it is located:
a. where the Eurasian plate descends beneath the Pacific plate
b. at the continental collision boundary between the Eurasian and Pacific plates
c. where the Pacific plate descends beneath the Eurasian plate
d. at the transform boundary between the Pacific and Eurasian plates

50. In an earthquake-prone region, the safest house would be a:
a. log cabin built on bedrock
b. log cabin built on loose soil
c. brick house built on bedrock
d. brick house built on loose soil