Physical Geology

Test 2

Dale Easley

October 13, 1998

1. In a desert, the type of weathering that dominates is (a) chemical weathering (b) mechanical weathering
2. Limestone dissolves in weak acid. In a wet climate, limestone is weathered primarily by (a) chemical weathering (b) mechanical weathering
3. When the roots of trees break the sidewalks in New Orleans, the breakage is an example of (a) chemical weathering (b) mechanical weathering
4. Sinkholes are primarily a result of (a) dissolution (b) glaciation (c) hydrolysis (d) oxidation
5. Unlike most chemicals, water expands when it freezes. Which of the following does this not influence? (a) floating ice (b) frost wedging (c) mechanical abrasion (d) nearly constant water temperatures near the bottom of deep lakes
6. Rust is an example product of (a) dissolution (b) glaciation (c) hydrolysis (d) oxidation
7. In Jamaica, accumulations of which of the following substances result from the large amount of rainfall which removes most other metals in the soil? (a) aluminum (b) gold (c) iron (d) silver
8. In which of the following locations is chemical weathering likely to be greatest? (a) New Orleans (b) Las Vegas, Nevada (c) Doha, Qatar (d) Phoenix, Arizona
9. Which of the following locations is likely to have the thickest soils? (a) on a steep slope (b) along a river in a valley (c) in a desert (d) in a rain forest
10. In the Nebraska Sand Hills, old sand dunes are now overgrown with grass. This is an indication that (a) birds droppings contain grass seed (b) farmers have irrigated the area (c) the Nebraska climate is wetter than when the dunes formed (d) the sand has weathered to clays
11. The dominant factor in the formation of a soil profile is (a) the amount of soluble material (b) the downward movement of water (c) the organic content (d) the type of vegetation growing at the surface
12. Which of the following has the most chemical weathering? (a) Earth (b) Mars (c) the Moon (d) Venus
13. Salt, such as is common beneath Louisiana, is an example of which type of sediment? (a) chemical sediment (b) detrital sediment
14. The Mississippi River Delta is composed of which type of sediment? (a) chemical sediment (b) detrital sediment
15. If a sand grain is very rounded, which of the following is most likely to be true? (a) It has not been transported far from its source. (b) It was made from a hard mineral. (c) It was transported a long distance by a stream. (d) It was transported by a glacier.
16. Which of the following locations is likely to have the coarsest sediment? (a) the bottom of Lake Pontchartrain (b) the Honey Island Swamp (c) the marsh near Jean Lafite National Historic Area, Barataria Unit (d) the natural levees along the Mississippi River
17. Which of the following rounds sediment the least? (a) glaciers (b) major rivers (c) mountain streams (d) wind
18. A rock that forms from very large, angular grains is called a (a) breccia (b) conglomerate (c) mudstone (d) sandstone
19. In the figure below, which (A-D) is the bedding plane?
20. In the figure below, which (A-D) are cross-beds?
21. In the figure below, which (A-D) is graded bedding?  
    
    
    
    
    
    
    
    
    
    
    
    
    
    

22. The Mediterranean Sea is underlain by thick salt deposits. They formed when (a) Continental collision forced deep salt deposits to the surface. (b) Hotter climates in the past caused more evaporation. (c) Large salt accumulations in Europe dissolved and washed into the Mediterranean. (d) The Mediterranean was separated from the Atlantic Ocean by a natural dam at the Straits of Gibraltar.
23. Which of the following is not a reason estuaries are particularly rich in marine life? (a) the estuary is protected from the force of the open ocean (b) nutrients are washed in from nearby land (c) sediments are well sorted (d) wastes are washed out to sea by tidal flow
24. The fine-grained ooze on the bottom of the deep oceans comes primarily from (a) the bodies of dead planktonic microorganisms (b) buried beaches (c) oil seeps (d) volcanic activity
25. Which of the following is not a reason civilizations have commonly developed on river deltas? (a) the construction of levees requires advanced engineering (b) rivers supply fresh water for irrigation (c) sediments from yearly floods are rich in nutrients for growing crops (d) transportation by water is nearby
26. In the figure below are three zones of metamorphism, marked A-C. Which represents metamorphism under high-temperature but low-pressure conditions?
27. In the same figure, which represents dynamothermal metamorphism?  
    
    
    
    
    
    
    
    
    
    
    
    
    
    

28. Directed pressure is primarily a result of (a) circulating fluids (b) deep burial (c) high temperature (d) plate collisions
29. A migmatite is a rock that is part igneous and part metamorphic. This results because of (a) the development of cleavage in rocks. (b) the different melting points of mafic and felsic rocks (c) the presence of mica (d) rapid cooling near an igneous intrusion
30. In the figure below, which is the oldest feature (A-E)?
31. In the figure below, what is the youngest feature(A-E)?
32. In the figure below, what is the feature labeled X? (a) angular unconformity (b) disconformity (c) nonconformity (d) uniformity  
    
    
    
    
    
    
    
    
    
    
    
    
    
    

33. Which of the following is oldest? (a) a sedimentary rock (b) the sediment the sedimentary rock was formed from (c) a crack in the sedimentary rock
34. Rock unit X contains dinosaur bones. Rock unit Y human bones. Which of the following can we say? (a) X correlates to Y (b) X and Y are the same age (c) X is older than Y (d) X is younger than Y
35. A radioactive element releases 2 protons and 2 neutrons. Which of the following is not true? (a) the element and isotope both change (b) the element stays the same but the isotope changes (c) the atomic mass decreases by four (d) the atomic number decreases by two.
36. A substance has a have life of 50 years. If I start with 2kg of the substance, after 150 years I will have (a) 1kg (b) 0.5kg (c) 0.25kg (d) 0.125kg
37. Weathering may affect radiometric dating by removing some of the parent or daughter products of decay. If weathering removes more of the daughter product of a substance than of the parent, an age obtained from the weathered sample will appear to be (a) younger than it really is (b) older than it really it
38. Which of the following evolved first? (a) blue-green algae (b) sharks (c) alligators (d) rats
39. Which of the following is not a reason why coal forms from old swamps? (a) Coal is formed from plant remains. (b) Swamps provide an environment where little oxygen is available for the decay of plants. (c) The burial of the plants provides the high heat and temperature necessary to convert them to coal. (d) Coal is formed from the shells of swamp-dwelling organisms.

    
    

    
    For the following questions, darken A for true, B for false.

    
    

40. A more angular grain of quartz is likely to have traveled farther from its source than a more rounded one.
41. Soil develops a bright red color when it spends most of the year submerged in water.
42. A stalagmite forms on the ceiling of a cave.
43. Reefs form along coasts where there is a large amount of sediment in the water coming from nearby rivers.
44. The collision of two continents would lead to the production of sediment rich in volcanic fragments.
45. Foliated rocks result from directed pressure.
46. All most all regional metamorphism is caused by plate tectonics.
47. Tree-ring dating can be used to estimate the age of dinosaurs.
48. Humans evolved at approximately the same time as dinosaurs.
49. Soil erosion is no longer a problem in the United States.
50. The Earth is estimated to be 4.6 million years old.

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