Physical Geology

Test 1

Dale Easley

Fall, 1998

Mark your answers on a blue scantron.

1. The Theory of Uniformitarianism states that (a) All things occur at a uniform rate. (b) School students should wear uniforms. (c) The past is the key to the present. (d) The Earth is only a few thousand years old.
2. The father of modern geology was (a) Francis Bacon (b) James Hutton (c) Aldous Huxley (d) John McPhee
3. If a scientist must choose between two or more hypotheses, the scientist will choose (a) the simplest one (b) the one that best explains observations (c) the one most popular in opinion polls (d) the one most difficult to understand
4. The first step in the Scientific Method is to (a) determine what you believe (b) develop hypothesis (c) determine which of competing hypotheses best explains observations (d) gather data
5. The brittle outer portion of the earth which includes the continental plates is called the (a) asthenosphere (b) lithosphere (c) mantle (d) Moho
6. Which of the following locations is most likely to experience an earthquake? (a) in the middle of an oceanic plate (b) in the middle of a continental plate (c) where a continental and oceanic plate meet (d) deep in the mantle
7. At the mid-oceanic spreading centers, which of the following does not occur? (a) mafic lava comes out (b) new oceanic crust is created (c) earthquakes are common (d) subduction zones
8. Which of the following is not believed to have caused the extinction of the dinosaurs? (a) impact of a meteorite (b) massive volcanic eruptions of India's Deccan plateaus (c) a combination of a and b (d) neither a nor b
9. After studying the formation of the solar system, which of the following planets would you expect to be composed primarily of heavy elements? (a) Jupiter (b) Mercury (c) Neptune (d) Saturn
10. The solid portion of the earth made mainly of iron and nickel is (a) the crust (b) the inner core (c) the mantle (d) the out core
11. Which of the following is an example of the term relative dating, as used by geologists? (a) checking someone's ID before letting them in a bar (b) determining if Monica Lewinsky was underage (c) finding out if someone you're interested in is older or younger than you (d) getting picked up at a family reunion
12. During the iron catastrophe, (a) a comet made mostly of iron hit the earth, destroying the dinosaurs (b) dense, molten iron sunk the the center of the earth (c) iron oxidized, forming rust (d) iron fused, generating the heat that powers the sun
13. When an oceanic plate meets a continental plate, the reason that the oceanic plate is pushed beneath the continental plate is that (a) circulation cells in the asthenosphere pull the oceanic plate downward (b) the continental plate is brittle (c) the oceanic plate is denser (d) the oceanic plate is moving but the continental plate is not
14. Which of the following is the result of the collision between two continental plates? (a) Crater Lake (b) Hawaii (c) the Himalayas (d) Mt. St. Hellens
15. When sodium chloride is formed (table salt) the sodium atom (a) becomes conductive of electricity (b) gives up an electron (c) loses a proton (d) shares an electron with the chlorine atom
16. The mass of an element is determine by the number of (a) neutrons and electrons (b) protons (c) protons and electrons (d) protons and neutrons
17. The most important parts of an element for bonding are (a) electrons (b) neutrons (c) protons (d) b and c
18. If a mineral has multiple forms, it is called (a) effervescence (b) metallic (c) a mineraloid (d) polymorphic
19. What property of a mineral is least likely to help identify it? (a) color (b) hardness (c) luster (d) streak
20. About what percentage of the crust do silicates make up? (a) <10 (b) 25 (c) 50 (d) >90
21. Which of the following minerals is made of silica tetrahedra bonded together as sheets? (a) diamond (b) feldspar (c) quartz (d) mica
22. Amethyst is a type of quartz but has a beautiful color that is due to (a) exposure to radiation (b) exposure to ultraviolet light (c) impurities (d) its cleavage
23. What common sulfate mineral is used in making sheetrock? (a) gypsum (b) limestone (c) platinum (d) quartz
24. When comparing diamond and graphite, which of the following is not true (a) the amount of water included in them is different (b) their composition is different (c) the pressure at which they formed was different (d) the temperature at which they formed was different
25. Under Florida are rocks that dissolve easily in the weak acid of rainwater, forming caves and sinkholes. These rocks are (a) iron oxides (b) limestones (c) quartz sandstone (d) sulfates
26. If one sees calcite, a soluble mineral common to limestone, filling fractures in a granite, the calcite was probably deposited from (a) cooling of water in fractures (b) melting from high heat and pressure (c) migration of magma (d) a volcanic eruption
27. Which of the following has the highest melting point? (a) felsic rock (b) intermediate-compostion rock (c) mafic rock (d) a,b, and c
28. Which of the following is least dense? (a) felsic rock (b) intermediate-compostion rock (c) mafic rock (d) a,b, and c
29. Which of the following is produced from magma of the lowest viscosity? (a) felsic rocks (b) intermediate-compostion rocks (c) mafic rocks (d) a,b, and c
30. Which of the following is likely to be lightest in color? (a) felsic rock (b) intermediate-compostion rock (c) mafic rock (d) a,b, and c
31. The oceanic crust is made of (a) felsic rock (b) intermediate-compostion rock (c) mafic rock (d) a,b, and c
32. The lunar marie (or ``seas'') are formed from (a) felsic rock (b) intermediate-compostion rock (c) mafic rock (d) a,b, and c
33. Andesite is an intermediate-composition extrusive igneous rock. At which of the following locations is it most likely to occur? (a) at a mid-oceanic hot spot (b) where two continents collide (c) where two oceanic plates collide (d) where an oceanic and a continental plate collide
34. If we were attempting to separate an intermediate-composition rock into mafic and felsic components, the method we would likely use is (a) compress the rock to 100 atmospheres (b) heat the rock to 1000 degrees centigrade (c) induce a vacuum around the rock (d) submerge the rock in ocean water
35. Which of the following is not a difference between intrusive and extrusive mafic rocks? (a) composition (b) crystal size (c) the pressure they were under when they cooled (d) the rate at which they cooled
36. Which of the following is not a source of heat for the creation of magma? (a) decay of radioactive isotopes (b) frictional heat produced as the plates move against each other (c) heat produced during the formation of the earth (d) nuclear fusion
37. What is a xenolith? (Remember in class when I mentioned xenophobes.) (a) a domed intrusion in other rocks (b) a large body of rock formed form the slow cooling of magma (c) a piece of preexisting rock incorporated without melting into the magma (d) a massive pluton
38. At which of the following locations are basalts not commonly found? (a) continental rifts, such as the Rift Valley in Africa (b) interior of a continent (c) mid-oceanic hot spots (d) shield volcanoes
39. If magma has high gas content and high viscosity, then an eruption from it will likely (a) flow rapidly downhill (b) explode violently (c) form shield volcanoes (d) a and b
40. If a volcanic eruption forms both pahoehoe and aa, then (a) the lava is probably felsic instead of mafic (b) the aa will form further along the flow as the lava cools (c) the aa and pahoehoe are likely to me intermingled (d) it is the result of a particularly violent eruption
41. Which of the following is an indication of an impending volcanic eruption? (If you didn't attend class, you won't know this.) (a) decrease in number of tremors (b) reduction in the amount of heat flow to the surface (c) changes in the composition of groundwater (d) a and b

    The test is continued on the back! Answer the following True/False questions with A for True and B for False.

    
    

42. A composite cone (or stratovolcano) is made from alternating layers of basalt and gabbro.
43. When two continental plates collide, they form a subduction zone.
44. Andesite is the most abundant rock at the Earth's surface.
45. The Theory of Catastrophism stated that which take place today are the same processes that have been operating in the past.
46. The inner core of the earth is solid because of the high viscosity of liquid iron and nickel.
47. Water raises the melting point of rocks.
48. The continents are made primarily of ultramafic rocks.
49. An ore is a rock with a high concentration of gemstones.
50. A lava plateau results form a large central-vent eruption.
51. A volcanic dome is usually formed from felsic magma.

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