{Note: these questions highlight important aspects of the reading, but please try to think in a more integrated "Earth System" way when reading. These processes are all interrelated and linked to the tectonic system.}
(1) What are the four main modes of sediment transport (i.e. materials that support and transport the sediment)?
(2) Explain the difference between the following transport mechanisms: suspension, traction, saltation, and bedload. How does settling velocity affect the transport mechanism?
(3) What is the "discharge" of a stream? What is the difference between turbulent and laminar flow?
(4) What is grain sorting and how can it come about in a river?
(5) In words, what is a graded stream? Sketch and label a graded stream profile. What is the effect on a graded stream of increasing the base level (i.e. damming the river)? How about of decreasing the base level? How about progressive uplift of the source region, perhaps by tectonic activity like faulting?
(6) Draw a sketch of a meandering river and show how it can be depositing sediment and eroding at the same time.
(7) Why are some rivers straight, some are braided, and some follow a meandering course.
(8) Explain (describe) the "life cycle" of a lake.
(9) What is a delta? Explain how a delta forms.
(10) What is a tidal flat?
(11) Why do oceans have waves? Why do waves break near the shore? Why do beaches have clean, well-sorted sand? What happens to the other types of sediment that is delivered to the coast by rivers (we don't see it on beaches)?
(12) What is long-shore drift?
(13) According to the book, what is a major difference between sediments made of carbonate and those made of silicate minerals?
(14) What are the three main types of sediment that one might find in the deep ocean? ... and where do they come from?
(15) What is a turbidite and how does it form?
(16) Is there a relationship between the type of plate boundary and the type of sediment that is deposited?
1) Detrital sediment components would not include A) shell fragments. B) quartz grains. C) authigenic minerals. D) lithic fragments. E) pyroclastic debris.
2) Which of the following is an example of chemical sediment forming a clastic deposit? A) granite cobble conglomerate B) calcite-cemented sandstone C) evaporite beds D) ignimbrite E) gypsum and sand dunes
3) The basic key to effective sediment erosion and transport by stream is A) water volume. B) turbulence. C) river length. D) stream gradient. E) bedrock type.
4) Which factor would not affect the settling velocity of particles in water transport? A) grain shape B) grain size C) grain density D) fluid viscosity E) fluid temperature
5) The bed load of a stream includes materials in ___________ and ___________. A) solution; suspension B) suspension; traction C) traction; saltation D) solution, saltation E) none of the above
6) Stream competency varies directly with stream A) cross-sectional area. B) volume. C) velocity. D) velocity squared. E) drainage basin size.
7) Which of these factors tends to be in a l mudflow? A) turbulence B) settling velocity C) density D) viscosity E) competency
8) The sedimentary transporting medium which carries the widest particle size range is A) a turbidite. B) wind. C) turbulent stream flow. D) glacial ice. E) mudflow.
9) Turbidites form as a result of the A) deposition of biogenic calcareous ooze on the sea floor. B) seasonal evaporation of water in shallow inland seas, leading to the development of fine, alternating layers of salt deposits. C) deposition of sediment by turbulent, gravity-driven flows that move swiftly from the edge of the continental shelf toward the deep sea floor. D) chemical precipitation of alternating coarse and fine layers of sediment in a shallow marine environment. E) cascade of sand down the steep face of a giant sand dune.
10) Bedforms are not characteristic of A) dunes. B) stream beds. C) the base of a glacier. D) beaches. E) the ocean floor.
11) Interaction between flowing water and its channel will control A) flow velocity. B) size of sediment supplied. C) volume of water. D) grain angularity. E) all of the above
12) Very well sorted sediments have a uniform A) grain size. B) grain shape. C) grain density. D) grain mineralogy. E) all of the above
13) Slow uplift of a graded stream leads to A) deposition. B) stream ponding. C) stream diversion. D) rejuvenation. E) all of the above
14) Raising sea level will cause a stream to A) backfill its channel. B) flow faster. C) lengthen its channel. D) increase downcutting. E) all of the above
15) A graded river which extends its length by depositing a delta will have to ___________ sediment in its landward reaches. A) deposit B) erode C) acquire new D) transport more E) all of the above
16) Stream piracy is most common in A) headwaters regions. B) low gradient streams. C) the Caribbean. D) faulted stream beds. E) the Mississippi.
17) The only thing which is currently keeping the Mississippi River main channel from jumping into the Atchafalaya River is A) gravity. B) a drought. C) the Army Corps of Engineers. D) its steeper gradient. E) all of the above
18) Which stream situation is least likely to leave a sedimentary record? A) delta channel B) waterfall plunge pool C) braided stream D) ponded stream E) meandering stream
19) Which stream characteristic does not pertain to braided channel settings? A) multiple channels B) steeper slope C) mostly sand and gravel sediment D) sparse vegetation E) low discharge
20) Valleys with meandering rivers are typified by A) oxbow lakes B) a single flow channel C) significant relief D) elevated flood plains E) all of the above
21) Which of these fossil fuel deposits is a resource not currently in production? A) oil shale B) oil C) peat D) coal E) natural gas
22) Lakes in warm, moist climates tend to disappear quickly because of A) high evaporation rates. B) detrital fill. C) high organic productivity. D) dam failure. E) all of the above
23) Catastrophic drainage of Lake Bonneville created the A) Great Salt Lake. B) Green River shales. C) Columbia River outwash plain. D) channeled scablands. E) Snake River.
24) The organic material in the Green River oil shales is derived mostly from A) trees. B) fish remains. C) inorganic carbon. D) algae. E) shoreline vegetation.
25) Lacustrine sedimentary features which are enhanced by seasonal ice cover are A) varves. B) symmetrical ripples. C) salt layers. D) moraines. E) coal beds.
26) The arid climate counterpart to a delta is a (an) A) meander. B) alluvial fan. C) mudflow. D) levee. E) point bar.
27) Desert flash floods are highly erosive because of their A) steep channels. B) high velocities. C) sediment load. D) turbulence. E) all of the above
28) Base channel for a desert channel is A) sea level. B) its alluvial fan. C) the adjacent basin floor. D) the closest dam. E) a desert dry lake.
29) Alluvial fan sediments could never be described as A) mudflow deposits. B) poorly bedded. C) poorly sorted. D) flash flood deposits. E) mature.
30) The feature which makes up that most area of the world's desert is A) dune fields. B) evaporite lakes. C) rocky plains. D) stream beds. E) alluvial fans.
31) The bottomset beds of an advancing delta are originally deposited on the A) delta plain. B) platform slope. C) ocean floor beyond the delta. D) distributary channel margins. E) none of the above
32) The most dominant process controlling overall delta morphology in the ocean is A) wave activity. B) the rate of sedimentation. C) sediment grain size. D) high river discharge. E) ocean currents.
33) Which sedimentary depositional environment is subject to the most wetting and drying events in a given period of time? A) a desert dry lake B) tidal flats C) an alluvial fan D) a flash flood channel E) a delta plain
34) The tidal flat evaporite mineral CaS _elementsubscript_element2 _elementsubscript_elementO is A) anhydrite. B) dolomite. C) calcite. D) gypsum. E) aragonite.
35) The baseline requirement in nature for beach formation is A) quartz grains. B) vigorous surf. C) longshore drift. D) a coast of submergence. E) all of the above
36) In the equation Q = Av, Q is A) deposition rate. B) quality. C) discharge. D) flow rate. E) quarter wavelength.
37) Preservation of primary bedding features could be a result of A) bottom stagnation. B) rapid deposition. C) a shifting depositional site. D) coarse sediment. E) all of the above
38) Deposition of marine sediments is slowest A) on the beach face. B) in lagoons. C) on tidal flats. D) on the shore face. E) far from shore.
39) Transportation and deposition of sediment by turbidity currents is commonly indicated by A) mud cracks. B) cross-bedding. C) graded bedding. D) ripple marks. E) horizontal laminae.
40) Marine invertebrates use calcium carbonate from seawater to build their shells because it is the most ___________ chemical available in seawater. A) abundant B) durable C) insoluble D) saturated E) attractive
41) The absence of ripples in sediment being transported by flowing water indicates that the flow regime is A) ripple. B) dune. C) plane bed. D) antidune. E) turbulent.
42) Which of the following features would most likely be found in the first cycle (that is, the lowest layer) of a turbidite? A) muds and clays B) conglomerates with extremely angular fragments C) graded beds D) erosion surface E) mudcracks
43) In general, what happens to discharge downstream? A) It decreases. B) It stays the same. C) It increases. D) It cannot be measured, so no one knows for sure. E) none of the above
44) The total area drained by a stream and its tributaries is a(n) A) tub. B) drainage basin. C) aquifer. D) drainage divide. E) lake.
45) Stream bars form A) where water velocity is lowest. B) on the outsides of bends in a stream channel. C) from dissolved ions in water. D) where water velocity is highest. E) where bass fishing boats congregate.
46) Which sequence of rock types would help you identify an ancient continental rift? A) thick beds of conglomerate, sandstone interbedded with lake deposits, evaporites and basalt flows B) thick deposit of shallow marine limestone and shale C) thin deposits of stream sediments and shallow marine mudstone and limestone with interlayered basalt flows D) turbidites mixed with deep sea oozes and pillow basalt E) conglomerate, sandstone, and landslide deposits
47) What is the most disadvantageous aspect of shallow agitated tropical waters for marine organisms? A) poor oxygenation of the water B) low nutrient supply C) lack of available carbonate for shell building D) wave action E) lack of sunlight
48) Organisms which secrete silica shells include A) diatoms, forams. B) radiolaria, diatoms. C) corals, marine snails. D) corals, diatoms. E) coccolithophorids, corals.
49) Most submarine canyons are A) near river mouths. B) turbidity current channels. C) on tectonically active margins. D) cut by headward erosion. E) all of the above
50) The major mechanism for transporting sediments to the continental rise and beyond is A) wind. B) longshore drift. C) turbidity currents. D) high storm waves. E) ocean currents.
51) The most constant factor depleting beach sand on all costs is A) submarine canyon turbidity currents. B) longshore drift. C) heavy storm waves. D) jetties. E) all of the above
52) Ripples formed by oscillatory currents, such as in a beach environment, are A) symmetric in profile. B) asymmetric in profile. C) never preserved in sedimentary rocks. D) only present during large storms. E) found only in the water itself.
53) Alluvial fan deposits form where A) streams flow out of mountainous channels onto a desert plain. B) mudcracks form in mud desiccated by intermittent exposure to the air. C) meltwater streams from glaciers deposit their contents. D) large rivers enter large bodies of water. E) major rivers flood over their banks.
54) Alternating layers of coal, shale, and sandstone would have been deposited in which of the following environments? A) delta plain and marsh B) alluvial fan C) submarine fan D) river beach E) shallow marine beach
55) The presence of potassium feldspar grains in sandstone indicates that A) the source area was gabbro. B) the original sand had no porosity. C) deposition was close to the granitic source. D) the source area was deeply chemically weathered. E) the rock is bioclastic.
56) Turbidites are not likely to show A) fine laminae. B) scour features. C) graded beds. D) bioturbation. E) immature texture. For the following questions, pick the plate margin environment in which the described deposits are most likely to originate.
57) Immature, diverse sediments in small, fault-bounded basins A) convergent B) divergent C) transform
58) Marine greywackes A) convergent B) divergent C) transform
59) Terrestrial arkoses covered by volcanics and then marine sediments A) convergent B) divergent C) transform 60) A negative aspect of dam construction is A) water storage. B) that it changes base level. C) hydroelectric power. D) flood control. E) recreation.
61) The rules of phase chemistry limit mineral assemblages in crystalline rocks, but not in sediments.
62) Evaporite deposits are composed of authigenic minerals.
63) The capacity of a stream is the maximum size of sediment clast that it can transport.
64) The more water a stream has, the greater its capacity to transport sediment.
65) Stokes' law accurately predicts the settling behavior of large grains in water.
66) A complete understanding of sediment behavior in water has not yet been accomplished.
67) Rock debris is translated upward in a glacier by plastic turbulence.
68) Accumulations of shell fragments are not sediment because they are organic.
69) A sand dune bedform is just a big ripple.
70) Antidunes differ from dune bedforms in that erosion takes place on the downstream side.
71) Variable flow velocity is more effective than constant velocity in sorting sediment.
72) A graded stream has the same gradient from headwaters to mout
73) The elevation at the mouth of a river may be at or above sea level.
74) After a dam is installed, the river responds by eroding its channel both upstream and downstream.
75) Draining a lake will raise base level upstream.
76) The water table is the lower surface of the zone of saturation.
77) In perennial rivers, the sediment concentration continually increases downstream.
8) Perennial rivers are spring-fed but ephemeral rivers are not.
79) Natural levees are flood stage deposits.
80) Lake sediments are widespread but generally unfossiliferous.
81) Rainwater is salty because it contains seawater.
82) Some 'freshwater' lakes have higher salinities than the ocean.
83) Tropical lakes are the most diverse in nutrients and biological make-up.
84) When a lake is initially formed, the water is rich in nutrients, but becomes depleted of them with time.
85) Delta plains only receive sediment at flood stage.
86) River-dominated deltas outnumber wave-dominated deltas worldwide.
87) Extensive tidal flats are more characteristic of passive than active margins.
88) Tidal flats show graded deposits from coarse sand inland to find muds offshore.
89) Beaches and tidal flats occupy the same shoreline position.
90) Longshore sediment transport can only be accomplished when wave trains approach the coast at an angle.
91) Longshore drift will deposit extra sand on the down current side of a groin.
92) The richest biological habitat along open beach coasts is the shoreface region.
93) Bioturbation preserves delicate depositional sedimentary structures in shallow marine sediments.
94) Sand bars have poor bedding because of their constantly shifting nature.
95) Shoreface sediments are deposited above wave base.
96) Most limestones, or carbonate rocks, are clastic rather than chemical sediments.
97) The bulk of carbonates are produced in the reef-lagoon complex.
98) Red and brown ocean bottom clays are latitudinally related to tropical laterite soils.
99) Chalk is a type of limestone derived entirely from siliceous phytoplankton.
100) The deposition of both carbonate and siliceous oozes is latitudinally controlled.
101) Both alluvial and submarine fans have sloping surfaces, but deltas are flat.
102) Passive margin marine sediments are mature because they have been derived from deeply eroded old mountain chains.