(1) What is mechanical weathering, and what are the main agents (processes) that foster mechanical weathering?
(2) What is chemical weathering?
(3) Discuss the feedback between mechanical and chemical weathering. Is it positive or negative feedback?
(4) Explain the interaction of carbonic acid and carbonate rock. How is this chemical weathering different from weathering of silicate rock? {Basically concerns what is left after the weathering process and how materials are transported away.}
(5) Draw a typical soil profile (with O, A, E, B, C, and R horizons), and define or explain each of the horizons.
(6) How can the process of weathering separate chemical elements that were once all together in the unweathered parent rock?
(7) Explain how soils represent an interaction of the plate tectonic, climate, biologic, hydrologic, and sediment systems (cycles).
(8) How can weathering account for the presense of mountains in our valley (e.g. Mt. Sugarloaf)?
1) The degree of chemical weathering of a particular rock depends upon A) temperature. B) availability of water. C) rock chemistry. D) climate. E) all of the above
2) The agent of mechanical weathering on the moon is A) meteorite impact. B) root wedging. C) erosional stress release. D) frost wedging. E) all of the above
3) Spheroidal weathering on the moon is A) chemical weathering. B) stream transport. C) mechanical weathering. D) the tropics. E) mid-latitudes.
4) Frost wedging is most effective in this environment. A) high polar regions B) Antarctic dry valleys C) deserts D) the tropics E) mid-latitudes
5) Which of the following is the best description of frost wedging? A) Water collects in natural cracks and crevices in rock and chemically weathers mineral grains in the rock. B) Frost wedging is the mechanical wearing and grinding of rock surfaces by glacial ice scraping along a bedrock surface. C) Mechanical weathering where water in rocks freezes, breaking the rock apart. D) Frost weding is a mechanical process where growing salt crystals in cracks widen the cracks and push grains apart. E) It is a process that transports grains downhill by rolling the grains along the ground surface.
6) The most pervasive primary pathways for water penetration in all rock types are A) crystal boundaries. B) bedding planes. C) joint planes. D) bands of weak minerals. E) fault planes.
7) The major change in granite produced by mechanical weathering is A) disintegration. B) alteration of crystal size. C) change in mineral composition. D) solution. E) abrasion.
8) Quartz is resistant to weathering because it has A) low temperature formation. B) covalent bonds. C) no cleavage. D) 3-dimensional bonding. E) all of the above
9) Hydrolysis selectively removes __________ from biotite. A) Si, O B) O, Fe C) Fe, Mg D) Si, Mg E) all of the above
10) Pure, distilled water has a pH value of A) 1. B) 3. C) 5. D) 7. E) 9
11) The acid in soft drinks, or sodas, is __________ acid. A) acetic B) carbonic C) hydrochloric D) sulfuric E) all of the above
12) Feldspars are more resistant to chemical weathering than micas because feldspars lack A) potassium. B) covalent bonds. C) Van der Waal bonds. D) low temperature formation. E) all of the above
13) Chemical weathering A) works from the inside out. B) is retarded when mechanical weathering increases surface area. C) works slower in highly fractured rocks. D) is most intense and rapid where cracks intersect. E) is a mechanical process.
14) The mineral family which results from weathering of feldspars is the A) clays. B) silicates. C) micas. D) amphiboles. E) carbonates.
15) Carbonate rock weathering is mostly a process of A) oxidation. B) dissolution. C) hydrolysis. D) hydration. E) all of the above
16) Limestone features which depend from cave ceilings are called A) stalagtites. B) stalagmites. C) stalacmites. D) stalactites. E) pendants.
17) Limestone topography marked by an abundance of sinkholes is called A) cave collapse terrain. B) karst. C) speleotopography. D) dimpled land. E) Kweilin surface.
18) Most groundwater is slightly acidic due to the atmospheric contribution of A) sulfur. B) chlorine. C) acid rain. D) carbon monoxide. E) carbon dioxide.
19) The last salt to precipitate from seawater during evaporation is A) sylvite. B) calcite. C) halite. D) gypsum. E) borax.
20) Salt accumulation in heavily irrigated soil is A) saltification. B) erosion. C) salinization. D) hydraulic action. E) abrasion.
21) The most nearly saturated of all the salts in the ocean is A) calcium carbonate. B) calcium sulfate. C) potassium chloride. D) magnesium carbonate. E) sodium chloride.
22) The term soil includes A) glacial moraine. B) laterite. C) pyroclastic debris. D) lunar regolith. E) beach sand.
23) The soil zone where accumulation of weathering products takes place is the A) Ozone. B) A zone. C) B zone. D) O and A zones. E) R and A zones.
24) The soil zones where the most active weathering takes place are the A) A and R zones. B) C and R zones. C) B and C zones. D) O and A zones. E) R and A zones.
25) An iron donor form chemical weathering would be the mineral A) quartz. B) plagioclase. C) olivine. D) orthoclase. E) muscovite.
26) Gabbros and granites contain approximately equal amounts of A) magnesium. B) calcium. C) iron. D) aluminum. E) platinum.
27) The most effective process for sorting elements in the outer Earth is A) transportation. B) weathering. C) magmatic differentiation. D) sedimentation. E) sedimentary differentiation.
28) Which of these processes is not a kind of weathering? A) chemical B) mechanical C) frost wedging D) abrasion E) divergence
29) Which of the following minerals would be most susceptible to chemical weathering at Earth's surface? A) quartz B) biotite C) feldspar D) olivine E) mica
30) Meteorite craters are more obvious and abundant on the moon than on Earth because A) meteorite impacts have always been rare on Earth. B) the moon already had the craters when it was captured by Earth's gravitational field. C) surficial features like impact craters are worn down by weathering and erosion over time. D) the moon is larger than Earth and attracts more space-born objects. E) most craters on Earth have been filled in by sediment.
31) Differential weathering involves variable weathering rates based on A) rock type. B) climate. C) rainfall. D) location. E) culture.
32) On Earth, precipitation minima occur at A) 30e, and the poles. B) 30e. C) the equator and the poles. D) 30e and 60e. E) 60e.
33) The key factor for all weathering reactions on Earth is A) rock type. B) temperature. C) availability of water. D) pressure. E) grain size.
34) In mid-latitude areas, the soil profile is characterized by A) increased pH. B) well developed B horizon. C) clear C/R zone break. D) thin O zone. E) all of the above
35) A concentration of clay minerals in the B soil zone of middle latitudes is called A) calcrete. B) clichee. C) hardpan. D) silcrete. E) none of these
36) Weathering proceeds most rapidly in the tropics because of A) temperature. B) water availability. C) animal activity. D) plant activity. E) all of the above
37) Rivers which drain tropical regions are typically stained dark from A) iron. B) calcium. C) potassium. D) organic material. E) all of the above
38) The major acid rain components contributed by coal-burning plants are A) ammonia, sulfur. B) carbonic, sulfuric. C) sulfuric, nitric. D) nitric, carbonic. E) ammonia, methane.
39) Acid rain A) kills fish. B) kills forests. C) increases weathering of buildings and bridges. D) costs the governments and citizens a lot of money. E) all of the above
40) Chemical weathering is synonymous with disintegration.
41) Frost wedging occurs because water, like most fluids, expands upon freezing.
42) The rate of chemical weathering is strongly dependent upon the amount of mechanical weathering.
43) Weathering is a set of processes that move rock toward equilibrium.
44) A high-temperature mineral is more resistant to weathering than one that forms at a lower temperature.
45) Orthoclase is more vulnerable to weathering than calcium plagioclase.
46) A weak acid has few acid molecules in solution.
47) Seawater is slightly acidic, with a pH of 8.
48) Seawater contains more dissolved calcium ions than dissolved chlorine ions.
49) In a weathering 'acid attack,' hydrogen ions replace mineral cations.
50) Weak acids are more important in natural chemical weathering than strong acids.
51) Carbonate rocks don't react with water in weathering because they formed in water originally.
52) Groundwater that percolates through limestone becomes saturated in calcium carbonate.
53) Release of sodium or potassium ions by weathering increases groundwater acidity.
54) Biologic processes contribute to the (OH)- concentration of groundwater.
55) Chemical weathering is basically the replacement of mineral cations with hydrogen ions.
56) Ocean waters have apparently maintained a steady chemical balance since they formed.
57) Soils are composed exclusively of organic matter and decomposed minerals.
58) Minerals weather in the same order that they crystallize in Bowen's Reaction Series.
59) Sandstone that plots near its parent rock on a triangular composition diagram would be considered immature.
60) Reprocessing of sediments increase their maturity index.
61) Soil formation proceeds most effectively in a tectonically active environment.
62) The depth of weathering in inversely proportional to the rate of erosion.
63) Low-lying cratonic areas will be stripped of soil compared to tectonically active areas.
64) Salt cracking is caused by chemical reactions between salt and rocks.
65) On exposure at Earth's surface, a plutonic rock such as granite is usually far from its former equilibrium condition.
66) Passive margins are dominated by sedimentation rather than erosion.
67) Mature sediments are more typical of active than passive margins.
68) The presence of lithic fragments is an indicator of sediment immaturity.
69) Water vented volcanic eruptions tends to be highly acidic.
70) Vegetation and weathering are essentially separate factors in rock decay.
71) Desert sand grains are frosted primarily because of chemical etching.
72) Desert varnish results from the removal of the heavy metal cations Fe and Mn.
73) In the permafrost zone, lichens are the major cause of weathering.
74) Regolith is produced more by mechanical than chemical weathering.
75) In tundra environments, chemical weathering at the surface proceeds slowly because liquid water is scarce.
76) Boreal (northern subpolar) areas are noted for their relatively thick soil development.
77) Weathering necessarily involves removing grains from the site of weathering.
78) Deeply weathered tropical soils are richly endowed for agriculture.
79) Red bauxite is called laterite.
80) Soil conditions in tropical zones are strongly basic in chemistry.