(1) What is ore and has is it extracted from the earth?
(2) How do each the following processes lead to concentration (or exposure) of the noted economic mineral or material:
- Magmatic processes (chromite)
also discuss kimberlite
(diamonds)
- Hydrothermal processes (copper, silver, zinc, lead, gold etc..)
Where does the source
rock composition come into this?
- Sedimentary processes - manganese nodules, banded iron formation
Define "placer" and tell
how they lead to deposits of gold, diamonds, tin and others.
- Weathering processes (aluminum)
Also, diamonds!
(4) Explain the process by which coal is formed (the depositional environment, means of concentration, and evolution into coal)? Why does coal occur with different grades (i.e. lignite, bituminous, anthracite)?
(5) Discuss the 4-step process by which oil is formed (source rock, maturation, expulsion, entrapment).
(6) How is geophysics used to prospect for oil?
(7) What is geothermal energy? How do we tap this energy?
(8) Where in the world (tectonically speaking) is it most economical to exploit geothermal energy?
Choose the one alternative that best completes the statement or answers the question.
Match the ore-forming processes in A through D with the specific ore deposit types described below.
1) Placer gold A) magmatic B) sedimentary C) hydrothermal D) weathering
2) Porphyry copper deposits A) magmatic B) sedimentary C) hydrothermal D) weathering
3) Bauxite A) magmatic B) sedimentary C) hydrothermal D) weathering
4) Primary chromite deposits A) magmatic B) sedimentary C) hydrothermal D) weathering
5) Gold in quartz vein A) magmatic B) sedimentary C) hydrothermal D) weathering
6) Kimberlite diamond pipes A) magmatic B) sedimentary C) hydrothermal D) weathering
7) Black smoker metal sulfide deposits A) magmatic B) sedimentary C) hydrothermal D) weathering
8) Banded iron formations A) magmatic B) sedimentary C) hydrothermal D) weathering
9) The presence of radon gas is an indicator of A) gold. B) pyrite. C) uranium. D) mercury. E) chromite.
10) The binding agent in cement is A) calcium oxide. B) calcium carbonate. C) calcsilicate. D) silica. E) gypsum.
11) Which rock would make the strongest, most stable aggregate for concrete? A) andesite B) pumice C) limestone D) gypsum E) schist
12) Kaolinite is formed by the chemical weathering of A) limestone. B) feldspar. C) quartz. D) augite. E) olivine.
13) Which material weathers to form clays? A) feldspar B) quartz C) limestone D) coal
14) Why is it important to understand the crystal structures of silicate minerals? A) It's not, really. B) Most economic ores are silicates. C) The silicates are common rock-forming minerals. D) The Earth is composed entirely of silicate minerals. E) none of the above Select the tectonic setting that is most likely to produce the ore deposits described below.
15) Salton Sea area, CA mineralized brines A) mid-ocean ridge B) magmatic arc C) transform faults D) continental rifting
16) Rare-metal-bearing carbonatite magmas A) mid-ocean ridge B) magmatic arc C) transform faults D) continental rifting
17) Porphyry copper deposits A) mid-ocean ridge B) magmatic arc C) transform faults D) continental rifting 18) Ophiolite copper deposits A) mid-ocean ridge B) magmatic arc C) transform faults D) continental rifting
19) Uranium is found in a wide variety of geologic settings because it is so A) common. B) heavy. C) easily mobilized. D) radioactive. E) easily oxidized.
20) The high silica ( _elementsubscript_element) content of water in springs and geysers in Yellowstone National Park is caused by A) groundwater passing through limestone. B) groundwater passing through basalt. C) groundwater passing through rhyolite. D) dissolved quartz sand that is dumped into the larger geysers by park officials. E) all of the above
21) Plants which form coal are A) terrestrial. B) rooted. C) macroscopic. D) cellulose-rich. E) all of the above
22) What sedimentary particles most likely play a major role in the accumulation of organic matter in sediments? A) sand B) clay C) cobbles D) boulders E) porphyroblasts
23) Which of the following factors is not necessarily important for the production of hydrocarbons? A) source rocks B) reservoir C) halite D) caprock or seal E) heat Match the fossil fuels in A through E with their descriptions below.
24) The most abundant fossil fuel A) coal B) oil C) shale oil D) tar sands E) natural gas
25) Fossil fuel that is mostly methane A) coal B) oil C) shale oil D) tar sands E) natural gas
26) Fresh water petroleum deposit A) coal B) oil C) shale oil D) tar sands E) natural gas
27) Liquid fuel formed in the marine environment A) coal B) oil C) shale oil D) tar sands E) natural gas
28) Terrestrial petroleum deposit depleted of volatiles A) coal B) oil C) shale oil D) tar sands E) natural gas
29) The fossil fuel with the highest carbon content is A) peat. B) lignite. C) bituminous coal. D) anthracite. E) graphite.
Match the stage of formation of a petroleum deposit with the process that causes it.
30) Large molecules are broken down into smaller ones A) source B) maturation C) migration D) entrapment
31) Basin formation and organic production A) source B) maturation C) migration D) entrapment
32) Pressurized movement of maturated petroleum A) source B) maturation C) migration D) entrapment
33) Concentration of an exploitable oil "pool" A) source B) maturation C) migration D) entrapment
34) Most seismic prospecting for petroleum is designed to reveal A) reservoir rock type. B) oil source rock. C) thermal maturity of the petroleum. D) the oil pool. E) a structural trap.
35) The most expensive method of petroleum exploration is A) surface mapping. B) drilling. C) seismic surveying. D) gravity surveying. E) magnetic surveying.
36) Barite mud is used in oil drilling A) because it is cheap. B) to prevent gushers. C) for lubrication only. D) because it is thixotropic. E) all of the above
37) Secondary recovery methods used in petroleum exploitation do not include A) pumping. B) horizontal drilling. C) water flushing. D) steam intrusion. E) fracturing.
38) Relative maturity of eastern Appalachian fossil fuel deposits is ascribed to their A) greater age. B) depth of burial. C) proximity to an ancient collision boundary. D) deeper iron erosion. E) all of the above
39) Most potable water on Earth resides in A) the ocean. B) behind dams. C) groundwater. D) streams and lakes. E) the polar caps.
40) The majority of fresh water in the U.S. is used for A) drinking. B) agriculture. C) mining. D) industry. E) domestic use.
41) The remote sensing method most commonly used to map the water table is A) surface mapping. B) magnetic surveying. C) seismic reflection. D) electrical resistivity. E) gravity surveying.
42) Most geothermal plant production is located at collision plate boundaries and in A) Yellowstone. B) the Imperial Valley. C) Iceland. D) the Sahara. E) Kansas.
Write 'T' if the statement is true and 'F' if the statement is false.
43) Stone tool manufacture predates ores melting in human history.
44) The manufacture of bronze requires both smelting and alloying process.
45) Iron is more difficult to smelt than copper because the chemical reactions are more complex.
46) A particular mineral deposit may lost its status as on ore body over night.
47) A laterite is a soil enriched in potassium and silicon.
48) The clay content of soil increases when granite undergoes chemical weathering.
49) Petroleum is generated mostly from microscopic, planktonic, marine plants.
50) Most organic matter is introduced into sediments after deposition.
51) The initial stage of petroleum formation is dominated by microbial activity.
52) Peak coal production on Earth came before most petroleum reserves today were formed.
53) Petroleum may be solid, liquid, or gas state.
54) Groundwater may be instrumental in the migration and trapping of petroleum.
55) Petroleum maturation is more rapid at a continental rift than at a convergent margin.
56) Small, deep, fault-bounded basins are common sites for petroleum formation on passive margins.
57) The lower the impedance contrast encountered in seismic surveys, the clearer the underground picture is.
58) Hydrocarbon migration is generally toward collision zones.
59) Earth maintains water on its surface because _elementsubscript_elementO molecules cannot escape its gravity.
60) Most of the Earth's free water was outgassed in its early history.
61) Once groundwater is depleted, it cannot be renewed.