FINAL EXAM

Dec. 8, 1994

Geols/Nats 107


Note that potassium (K), sodium (Na), Lithium (Li), Hydrogen (H) all form cations with a charge of +1. Also magnesium (Mg), and calcium (Ca) are +2. Aluminum (AL) forms a +3 cation while silicon (Si) forms a +4 cation. Meanwhile Oxygen (O) forms a -2 anion while fluorine (F) and Chlorine (Cl) form -1 anions. Note that various ions have the following radii: K is 1.38 , Na is 1.02 , CL is 1.81 .

1. Which one of the following statements is true about atoms? a) All atoms have the same number of protons, b) Mass is equally divided between the nuclear matter and the electrons, c) Mass is concentrated in the nucleus, d) a single ion is always electrically neutral, e) all statements are true.

2. How any protons in Thorium 232 (atomic number 90)? a) 90, b) 232, c) 322 d) 142, e) all are incorrect.

3. How many neutrons in that same Thorium? a) 90, b) 232, c) 322, d) 142, e) all are incorrect.

4. Calcium (atomic number 20) has how many electrons in its inner (closest) shell? a) 20, b) 10, c) 8, d) 0, e) 2.

5. Calcium has how many electrons in its second shell? a) 20, b) 10, c) 8, d) 0, e) 2.

6. Calcium has how many electrons in its 4th (most distant) shell? a) 10, b) 8, c) 0, d) 2, e) 1.

7. Which one of these chemical formulas of minerals is not possible? a) K2Al2Si4O8, b) Al2O3, c) KCl, d) SiO2, e) all are impossible.

8. How can quartz have the formula of SiO2 when it is entirely made of SiO4 tetrahedra? a) It is missing some of its oxygen atoms, b) It has "charge balancing" silicon cations scattered through its structure, c) Adjoining tetrahedra share oxygens at each corner, d) The assumption is wrong, its formula is actually SIO4, e) All of the above are incorrect.

9. Why is there no complete solid solution between NaCl (halite) and KCl (sylvite)? a) There are different charges on the cations, b) There are different charges on the anions, c) Sylvite is covalently bonded, d) The assumption is incorrect, there is a complete solid solution between the two of them, e) Na (sodium) and K (potassium) ions have quite different sizes.

10. What is the difference between Carbon 12 and Carbon 14? a) C14 has two more protons, b) C14 has two more electrons, c) C14 has two more neutrons, d) C14 has two more protons or neutrons, e) All of the above are incorrect.

11. What materials are characteristic of most soils? a) feldspar, b) clay minerals, and quartz, c) quartz but not clay, d) ferromagnesium silicates, e) mica.

12. How does the "B" soil horizon differ from the "A" horizon? a) the "B" horizon has much organic material, b) the"A" horizon is leached of soluble materials, c) the "B" horizon has much feldspar, d) the "B" horizon has unweathered rock materials, e) the "B" horizon is leached of soluble materials.

13. What is the approximate age of Earth? a) a few thousands of years old, b) a few millions of years old, c) one million years old, d) more than a billion years old, e) no research has been done on this issue.

14. What implication came from uniformitarianism? a) glaciers were once widespread, b) granite is a rock, c) the Atlantic ocean is young, d) the Earth is very old, e) streams caused a large amount of erosion.

15. Which mineral that is common in soils is in shorter than expected supply in sedimentary rocks? a) quartz, b) iron minerals, c) clay minerals, d) feldspar, e) ferromagnesium silicates.

16. Some parts of Alaska and Siberia were not glaciated. A likely explanation is: a) it was too warm there, b) sun spots, c) there was little snow fall there, d) these places were so high the glaciers could not reach them, e) Boris Yeltsin would not permit it.

17. If a stream segment is graded, this means that? a) there is no erosion whatsoever going on in the stream segment, b) there is no deposition whatsoever going on, c) the stream segment has a very steep slope, d) there is no net deposition or erosion going on in the illustrated segment, e) only a small amount of erosion is going on in the stream segment.

18. It is further true that through time as long as the stream stays graded, the gradient is: a) increasing, b) decreasing, c) first increasing and then decreasing, d) first decreasing and then increasing, e) staying the same.

19. If, on the other hand, erosion commences, then, as long as erosion continues, the gradient will: a) increase, b) decrease, c) first increase and then decrease, d) first decrease and then increase, e) stay the same.

20. On the other hand, if deposition begins, then, as long as deposition continues, the gradient will: a) increase, b) decrease, c) first increase and then decrease, d) first decrease and then increase, e) stay the same.

21. Let us assume the a dam is built in a graded region of the stream upstream from the graded segment decried. We can expect: a) net erosion to commence even further upstream than the dam, b) nothing different to happen upstream from the dam; dams are quite benign, c) erosion to commence downstream from the dam, d) net deposition to commence downstream from the dam, e) nothing to happen downstream from the dam.

22. Furthermore, upstream from the lake behind the dam: a) net erosion will spread upstream, b) net deposition will spread upstream, c) nothing different will happen, d) drainage will improve because of net erosion upstream from the dam, e) a) and d) are correct but not b) or c).

23. Which one is most nearly true about base level? It is: a) the height above sea level of the valley of all streams, b) the amount of dissolved bases (as compared to acids in runoff, c) the thickness of glaciers, d) the lowest level to which a stream can erode, e) the height above sea level of the toe of a landslide.

24. What happens to an irregularity (a knickpoint) at right angles to a stream with time? It: a) gets smaller, b) moves upstream, c) gets larger, d) stays the same, e) a) and b) are both correct but not c) or d).

25. According to the Bible (Ecclesiastes 1.7) "all the streams run to the sea, but the sea is not full; to the place where the streams flow, there they flow again." The conundrum expressed here is solved by understanding: a) chemistry of water, b) uniformitarianism, c) the hydrologic cycle, d) graded streams, e) erosion.

26. Which one of the following is true about the hydrologic cycle? a) evaporation from the sea is exactly equal to rainfall into the sea, b) rainfall into the sea is less than evaporation from the sea, c) rainfall into the sea is greater than evaporation from the sea, d) there is more water contained in rivers than is retained in glaciers, e) rainfall on land is exactly equal to rainfall on the sea.

27. If loose surface material contains particles of many different sizes (clay sizes through large boulders) and these particles are composed of many different rock types and have angular shapes an appropriate term for these materials is probably: a) loess, b) talus, c) till, d) alluvial fan, e) outwash.

28. These materials are likely to be: a) mountain stream deposits, b)-fluvial-glacial deposits, c) storm deposits on a beach, d) direct glacial deposits, e) a) and b) are correct but not c) or d).

29. Ice movement in a glacier can best be described as: a) laminar flow, turbulent flow, c) neither, ice is a solid and slides forward as a solid block, d) a mixture of laminar and turbulent flow, e) rapid.

30. Evidence of the nature of this movement is: a) the great amount of erosion accomplished, b) the failure of materials to mix in existing glaciers, c) the great amount of mixing of materials in glaciers, d) the observed great purity of glacial ice, e) none of the above are correct.

31. One way to get a minimum thickness of a past continental glacier is: a) to observe the highest point that is glaciated and determine the relief of the region, b) determine the amount of cracking of the bedrock - rocks are more cracked where glaciers are thick, c) determine the thickness of the glacial deposits, d) all glaciers are the same thickness so there is nothing to find out, d) determine the distance to the source and determine the average thinning of the glacier from there.

32. The correct answer to the question above depends on which assumption? a) ice is a solid and moves as such, b) ice in a glacier mostly behaves as a liquid, c) glacial ice is very cold and therefore exceptionally strong, d) the land surface slopes downhill from the source of a glacier, e) glaciers are slippery.

33. Why were there no major glaciers during the Pleistocene (recent past) in the southern continents? a) It didn't get cold in the southern hemisphere, b) the southern hemisphere is almost totally a desert so there was not enough snow there, c) coriolis force, d) the southern continents reach only to 20 degrees of south latitude, e) the southern continents get smaller as they get into higher latitudes.

34. As waves approach shore, motion of water (by waves) on the sea (or lake) bottom will begin when wave length is: a) ½ wave height, b) ½ water depth, c) ½ the distance to shore, d) ½ wave velocity, e) ½ wave acceleration

35. Out at sea (in deep water) a point within a wave moved by the waves would move? a) back and forth, b) up and down, c) in an ellipse, d) in a square, e) in a circle.

36. What is meant by L? a) wave period, b) wave frequency, c) wave shape, d) wave length, e) ½ wave length.

37. Which one of these is correct and gives evidence for plate tectonics? a) oceanic volcanic rocks are younger the farther they are from mid-oceanic ridges, b) all oceanic volcanic rocks are old, c) the ages of oceanic basalts are randomly distributed, d) oceanic basalts are older the farther they are from mid-oceanic ridges, e) ages of volcanics are not related to their distance from mid-oceanic ridges.

38. Which one is true about the thickness of oceanic sediments as one travels away from a mid-oceanic ridge? a) they get thicker, b) they get thinner, c) they stay the same thickness, d) the thickness varies randomly, e) they get thinner, then thicker, then thinner

39. The reason for the correct answer above is that: a) the ocean bottom gets older away from ridges, b) the ocean bottom gets younger away from ridges, c) the ocean bottom is the same age everywhere, d) ocean bottom currents have variable strength, e) ocean bottom currents are stronger in shallow water

40. The age of the oldest sediments on the ocean bottom is what relationship to the mid-oceanic ridges? a) older away from the ridges, b) older toward the ridges, c) the same age everywhere, d) randomly distributed, e) much younger than the ridges.

41. What is the age relationship of the oceanic rocks to older continental rocks? a) continental rocks are younger than most oceanic rocks, b) continental rocks are the same age as most oceanic rocks, c) older continental rocks are a little older than most oceanic rocks, d) older continental rocks are much older than oceanic rocks, e) all of the above are incorrect

42. What is happening to the size of the Atlantic Ocean at the present time? a) it is pulsating -- first getting larger and a few hours later getting smaller, b) it is getting smaller, c) it is staying the same size, d) it is unknown what is happening, e) it is getting larger.

43. What kind of rock is erupted by volcanoes on mid-oceanic ridges? a) granite, b) rhyolite, c) basalt, d) andesite, e) obsidian

44. What kind of rock is erupted in volcanoes near the Pacific coast of land masses ringing the Pacific Ocean? a) granite, b) rhyolite, c) basalt, d) andesite, e) obsidian.

45. What do continental rocks have that oceanic rocks do not have? a) more quartz, b) more orthoclase feldspar, c) lower density, d) less iron and magnesium, e) all are correct.

46. What are transform faults usually associated with? a) trenches, b) mid-continental areas, c) mid-oceanic ridges, d) andesitic volcanoes, e) rhyolitic volcanoes.

47. As waves approach shore they will: a) not change, b) refract, c) accelerate, d) gain energy, e) be stopped by wind.

48. The result will be: a) waves will tend to hit shore almost parallel to shore, b) waves will hit shore in the same direction as originally propagated, c) waves will hit shore with greater energy than they had at sea, d) waves will hit shore almost at right angles to shore, e) waves will hit shore at a 45 degree angle.

49. The state of Maine has a very irregular shoreline. A good explanation is: a) wave erosion, b) sea level recently dropped, c) sea level recently rose, d) a) and b) are both correct but not c), e) none of the above are correct.

50. Where would one expect to find lateritic soils? a) glaciated regions, b) temperate climates, c) tropics, d) deserts, e) all are correct.

51. What age is the bulk of the "banded iron formation"? a) older than the oldest known rock and connected with the so-called iron catastrophe, b) Precambrian, c) early Paleozoic, d) late Paleozoic, e) Mesozoic.

52. What first caused O2 to increase significantly? a) algae, b) volcanoes, c) earthquakes, d) angiosperms, e) metazoans.

53. As O2 was increasing, what was decreasing? a) N, b) O3, c) CO2, d) H2O, e) nothing.

54. When did life first occur? a) Archean, b) at the Archean/Proterozoic boundary, c) late Proterozoic, d) Cambrian, e) early Paleozoic.

55. What is the first earthquake wave to arrive at a seismic station? a) L wave, b) S wave, c) X wave, d) SS wave, e) P wave.

56. Which wave will not penetrate the outer core of the earth? a) P wave, b) S wave, c) no wave can penetrate the outer core, d) all waves penetrate the outer core, e) all waves penetrate the outer core but do so slowly.

57. What happens to the P wave in the outer core of the Earth? a) It does not enter the outer core, b) it speeds up, c) it does not change velocity as it passes through the outer core, d) it slows down, e) No one knows what happens.

58. What is the nature of the inner core of the Earth? a) liquid, b) gas, c) solid, d) mixture of liquid and gas, e) vacuum.

59. What is an epeiric sea? a) a hyper-saline bay, b) relatively deep, small lakes, c) ancient deep oceans, d) a mirage, e) relatively shallow, geographically widespread sea.

60. What is a transgressive sea? a) one that is expanding, b) one that is getting smaller, c) one that is staying the same size, d) one that is not understood, e) a sinful sea full of sperm from copulating fish.

61. How did Pratt come to discover isostasy? The plumb bob was deflected toward the Himalayas: a) exactly as predicted by the law of gravity, b) too much, c) too little, d) it wasn't attracted -- it was repelled, e) none are correct.

62. The conclusion from this was that: a) the mountains were hollow, b) the mountains were more massive than they appeared to be, c) the mountains were less massive than they appeared to be, d) the mountains were exactly as they appeared to be, e) the mountains were in a different position than they appeared to be.

63. What did Cavendish's work on the gravity constant reveal about the interior of Earth? a) Earth is homogeneous, b) Earth is lighter at depth, c) isostasy, d) the crust is lighter than the interior, e) Newton was wrong.

64. What is the commonest mineral in the Earth's crust? a) granite, b) basalt, c) quartz, d) feldspar, e) clay.

65. Fig. 1 shows a partially filled out classification chart of the igneous rocks. Which point (1, 2, 3, 4, or 5) represents a rock with the same texture (grain size) as granite? a) 1, b) 2, c) 3, d) 4, e) 5

66. Which point represents a rock with the same composition as granite? a) 1, b) 2, c) 3, d) 4, e) 5

67. In general, what is the most important factor causing textural differences in igneous rocks? a) amount of iron, b) chemical composition, c) rate of cooling, d) radioactivity, e) gravity

68. What is a porphyry? a) an igneous rock with trapped gasses in holes, b) a very coarse grained igneous rock, c) a metamorphic rock without platy minerals, d) an igneous rock with two grain sizes, e) none of them

69. What causes a porphyry? a) eruption and fast cooling after partial crystallization underground, b) partial melting under high pressure, c) very fast cooling, d) very slow cooling, e) moderately fast cooling

70. Which of one the following extrusive rocks would be most likely to lead to a violent eruption if the preceding magma was made of the same material, except melted - make sure the material is reasonable? a) rhyolite, b) basalt, c) gabbro, d) limestone, e) none of them

71. Why so? a) rhyolite is more viscous and traps gasses, b) basalt is more viscous and traps gasses, c) gabbro is darker and this absorbs light energy -- the cause of volcanism, d) limestone is always made of obsidian, e) volcanos are never violent

72.

73. If there was 2 grams of U235 to start, how much would be left after 2 half lives? a) 1 gram, b) ½ gram, c) 1/4 gram, d) 1/8 gram, e) 1/16 gram

74. If the first radioactive event in the decay of U 235 is to emit an alpha particle, then, after that particle is gone, what is the resulting atomic weight? a) 233, b) 231, c) 234, d) 235, e) 239

75. What did Boltwood not know about? a) atomic weight, b) alpha particles, c) half lives, d) the element uranium, e) isotopes

76. Lithium (atomic number 3 and atomic weight 7) would have how many neutrons? a) 10, b) 3, c) 7, d) 1, e) 4

77. What would be the charge on its ion? a) +1, b) -1, c) 0, d) +3, e) -3

78. What is the meaning of a comma (,) in a "formula"? a) the elements separated by the comma are present in equal amounts, b) ions of those elements have opposite charges, c) elements separated by the comma substitute freely for one another, d) elements separated by a comma cannot substitute for one another, e) elements separated by a comma always have radically different sizes

79. In what situation is C14 possibly useful to determine ages? a) in archeological sites a few thousand years old, b) any place there is fossils no matter how old, c) in volcanic rocks several million years old, d) in unmetamorphosed sedimentary rocks of all ages, e) all are correct

80. Which one is true about the long valley we walked down just after we climbed the hill at the toboggan slides? a) the gradient gets steeper down hill, b) the gradient gets less steep down hill, c) the slope gets more irregular down hill, d) the large boulders are moved by running water, e) stream erosion did not make the valley

81. Which one is true about the hill at 87th and western? a) the entire hill is an ancient sand dune, b) the hill is a reef in the Silurian rocks, c) the hill is an unaltered glacial deposit called a kame, d) the hill is largely a remnant of a moraine, e) the hill is a remnant of a delta of a former glacial river

82. In the southern U. S. there is a large negative gravity anomaly. What is true about this anomaly? a) it is explained by the topography, b) clearly, the underlying rocks there are denser than those elsewhere, c) it is explained by isostasy, d) there is a large wedge of light rock there without topographic expression, e) unfortunately, no drilling has ever taken place there so we have no description of the underlying rocks

83. Similar gravity anomalies occur: a) on the east coast of North America, b) on the west coast of Europe, c) on the west coast of Africa, d) associated with deep trenches in the Pacific, e) no where else

84. What encourages folding (as compared to faulting)? a) high hydrostatic pressure, b) water, c) weak rocks, d) slow acting forces, e) all are correct

85. What is convincing about the direction to the North magnetic pole, that continents have moved with respect to one another? a) the north magnetic pole has been observed to wander in historic times, b) magnetic poles have been observed to reverse every hundred thousand years or so, c) the magnetic pole position for every continent becomes different back through time, d) magnetic materials, if heated past the Curie point, lose any magnetic direction they had, e) none are convincing, after all continental drift is baloney

86. Which is the most likely setting for blue schists? a) metamorphosed rocks in the midcontinents, b) contact metamorphism under lava flows, d) metamorphism of subducted sediments, d) areas of especially high temperature metamorphism, e) areas of especially low pressure metamorphism

87. Where are deep earthquakes likely to be found? a) subduction zones, b)-mid-oceanic ridges, c) in the middle of continents, d) in places such as the east coast of North America that are trailing edges of continental blocks, e) in "hot spots" such as Hawaii

88. Why is the Pacific Ocean basin rougher topographically than the Atlantic basin? a) it is a young ocean, b) it is pretty much surrounded by subduction zones, c) it has active volcanos, unlike the Atlantic, d) the Atlantic is so shallow that storm waves have eroded its bottom, e) it is not true that the Pacific basin is rougher than the Atlantic, it is the other way around

89. What type of faulting occurs at the Mid-Atlantic ridge? a) normal faulting, b) reverse faulting, c) thrust faulting, d) all are correct, e) the type of faulting is unknown

90. Where do the older rocks on Earth tend to occur? a) in ocean basins near subduction zones, b) in the middle of continents, c) in the deeper parts of the ocean, d) at spreading ridges in ocean basin rocks, e) randomly and unpredictably throughout the Earth

91. Which of the following describes a "P" wave? a) vibrates back and forth parallel to the direction of propagation, b) the first arriving wave at a seismic station, c) will travel through liquids as well as solids, d) is the fastest moving wave, e) all are correct

92. Which of the following describes an "S" wave? a) vibrates back and forth parallel to the direction of propagation, b) the first arriving wave at a seismic station, c) will travel through liquids as well as solids, d) is the fastest moving wave, e) none are correct

93. Most energy in an earthquake is in the: a) P waves, B) S waves, c) L waves, d) PP waves, e) SS waves

94. Time/distance curves for earthquake waves (P, S, and L) received by a seismograph allow one to easily to determine from time lags between waves: a) strength of earthquakes, b) the direction toward an epicenter, c) the kind of faulting, d) the distance to an epicenter, e) the presence of a liquid core

95. Isostasy is the idea that: a) rocks are strong enough to support mountains, b) rocks are only strong enough to support light rocks such as granite, c) mountains are made of metamorphic rocks, d) surface rocks including mountains float on the denser materials below, e) continents are made of granite

96. What did Cavendish finally calculate after getting the universal constant of gravitation? a) the volume of earth, b) the distance of Earth from its moon, c) the density of earth, d) the weight of earth, e) the mass of the moon

97. Which is the highest temperature metamorphic rock? a) limestone, b) slate, c) green schist, d) blue schist, e) gneiss

98. Fig. 2 is of a facies map of the sedimentary rocks deposited in the late Ordovician. In the eastern U. S. which generalization is most nearly correct? The main source of the clastic sediments is: a) mountains caused by the collision of Africa with North America, b) erosion of central Canada, c) subduction caused mountains along the east coast, d) mountains caused by collision of North America with Europe, e) mountains caused by the collision of North America with South America

99. At the time shown the Iapetus ocean is? a) getting larger, b) getting smaller, c) staying the same size, d) finally can be called the modern Atlantic Ocean, e) finally destroyed

100. Which one is true (despite what the text says) abut the BIF? a) it is pure (unoxidized) iron, b) BIF is mostly a recent iron deposit, c) its formation served to suppress the increase in free oxygen, d) BIF is very rare, e) BIF only formed in the Archean times