Sedimentology Lecture Final Test

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SEDIMENTOLOGY FINAL TEST - 2010
1. Which of the following deep marine environments would most likely have SP logs with "nervous
patterns"? A.subaqueous slumps B.olistostromes C.submarine fan deposits D.turbidites E.none
of the above
2. Which of the following would have the widest and most gradational facies? A.Ramp model shelf
B.Drop off model shelf
3. Which of the following would not be diagnostic of a carbonate-rich middle shelf environment?
A.salinity less than normal seawater B.water depth from a few tens to 100-200 meters C.well
oxygenated water D.water temperature from 10 to 30°C
4. If tides predominate in an estuarine environment the coarser sediments will be A.onshore B.in
the center of the estuary and offshore
5. Most invertebrates live ? wave base. A.above B.below
6. Mudcracks, intraclasts, laminations and birdseye structures would be characteristic of the ? zone.
A.subtidal B.littoral C.supratidal
7. Fan-like bodies of sediment transported landward by water pouring through a temporary gap in a
coastal barrier are termed A.tidal inlets B.spit platforms C.tombolos D.washover fans E.berms
8. Poorly-drained delta swamps would be characterized by A.black mud and plant debris
B.bioturbated or thinly-laminated silt beds C.iron concretions D.all of the above E.none of the
above
9. A thick, laterally-restricted mass of pure or largely pure carbonate rock is termed a A.bioherm
B.biostrome C.stratigraphic reef D.ecologic reef
10. A facies succession from basal supratidal dolomites to rounded mollusc grainstones to angular
molluscan grainstone to molluscan wackestones and packstones with "normal" marine faunas and
capped by dark mudstones and wackestones would probably represent a ? facies.
A.transgressive carbonate ramp B.regressive carbonate ramp C.transgressive carbonate dropoff D.regressive carbonate drop-off E.transgressive restricted carbonate marine shelf
11. Deltaic sequences A.fine upward B.often contain cyclothems C.are well stratified in the lower
part and poorly stratified in the upper part D.all of the above E.none of the above
12. Peritidal complexes forming in hot, arid climates typically have A.large tidal ranges B.low
salinities C.many sea grasses D.domination by carbonate particles and also have clastics and
evaporites E.all of the above
13. Submarine canyon and fan-valley channel deposits may be filled by a.slope muds B.mass flow
conglomerates C.grain flow sands and turbidites D.pelagic muds E.all of the above
14. Deep-water carbonate buildups usually are dominated by ? corals and algae. A.hermatypic
B.ahermatypic
15. A rigid, wave-resistant topographic structure built by actively building and sediment-binding
organisms would be termed a A.ecologic reef B.stratigraphic reef C.bioherm D.biostrome E.all
of the above
16. Deeply-buried deep marine carbonate reservoirs may retain a high primary porosity due to
A.overpressuring B.geopressuring C.early introduction of hydrocarbons D.all of the above
E.none of the above
17. Normal salinity is approximately ? parts per thousand. A.10 B .20 B.35 C.45 D.60
18. Swimming organisms are termed A.benthonic B.infauna C.epifauna D.planktonic E.nektonic
19. Cold, dense water masses that flow along the lower parts of submarine slopes are termed
A.turbidites B.internal waves C.tides D.tsunamis E.contour currents
20. Deposits that consists of large blocks deposited beneath reefs, faults or glacial scarps are termed
A.contourites B.olistostromes C.subaqueous slumps D.turbidites E.submarine fans
21. Gently-sloping surfaces with gradients of 1:100 to 1:700 on the seaward sides of continental
slopes are termed A.abyssal plains B.spits C.berms D.continental rises E.none of the above
22. Tidal patterns are controlled by A.28 day cycles B.gravitational attraction by the moon
C.gravitational attraction by the sun D.coastal morphology E.all of the above
23. A lens-like body of organic origin embedded in a rock of different lithology is termed a
A.biostrome B.bioherm C.stratigraphic reef D.ecologic reef
24. Fluvial-dominated delta systems typically form hydrocarbon reservoirs that are A.dip-oriented
B.branching and lenticular C.isolated sand bodies D.all of the above E.none of the above
25. Autochthonous reef rocks consisting of tabular or lamellar fossils encrusting sediments would be
termed A.bindstones B.floatstones C.framestones D.rudstones E.bafflestones
26. Sedimentary structures deposited in tidal channels will differ from meandering river channel point
bars in that A.fluvial point bars thickness is determined by flood stages and tidal bars by mean
water depth B.fluvial point bars are submerged only during flood stages and tidal point bars are
submerged during each high tide C.tidal channel point bars contain marine invertebrates D.all of
the above E.none of the above
27. Which of the following would be most similar to alluvial fan deposits? A.deltas B.deep sea fans
C.tidal deltas D.washover fans E.abyssal plain deposits
28. Drowned alpine glacial valleys are termed A.tombolos B.spits C.barrier islands D.estuaries
E.fjords
29. Which of the following reef zones would most likely develop bafflestones and floatstones within
tranquil water conditions? A.reef crest B.reef front C.fore reef D.reef flat E.back reef
30. A climate characterized by the presence of calm seas ("Doldrums") is A.tropical B.subtropical
C.temperate D.subpolar E.polar
31. Storm surges are A.due to hurricanes B.characterized by wind set up C.followed by gravitational
outflow through washover channels and tidal inlets D.creators of hummocks and swales E.all of
the above
32. Eperic seas A.are submerged continental margins B.are also termed pericontinental platforms
C.were predominant in the Cretaceous D.all of the above E.none of the above
33. A peritidal environment that is always under water is termed A.subtidal B.intertidal C.supratidal
34. An ephemeral feature on the upper beach built by sediment brought landward by swells is termed
a A.runnel B.swale C.berm D.spit E.swashbar
35. If a sequence consists of basal seaward-dipping beds followed by well-laminated horizontal
sands, followed by steep, landward-dipping beds and capped by dark gray clay the sequence
probably represents a A.transgressive peritidal B.regressive peritidal C.transgressive spit/barrier
island D.regressive spit/barrier island E.transgressive shelf
36. Carbonate-rich middle shelf environments are A.dominated by carbonate mudstones and
wackestones B.contain patch reefs and sand shoals C.have extensive nodular and irregular
beds due to bioturbation D.have interbedded shale and limestone/dolomite E.all of the above
37. Deltas with irregular geometries and in which elongate, dip-oriented sand bodies are formed by
reworking channel-mouth deposits within the distributary channels would be ? deltas. A.fluvialdominated B.tide-dominated C.wave-dominated
38. Which of the following would not be true for restricted carbonate shelves? A.formed due to a
physical barrier B.slow water circulation C.normal salinity D.depleted nutrients E.all of the
above are true for restricted carbonate shelves
39. Sea marginal sabkhas are characterized by A.shrinkage polygons B.fenestral structures,
C.nodular anhydrite D. "chicken wire" structures E.all of the above
40. Tidal channels are most similar to ? environments. A.lacustrine B.eolian C.braided stream
D.meandering stream E.pelagic
41. Distributary channels A.are formed where deltas discharge into the sea B.narrow and become
deeper seaward C.are characterized by the absence of deformation structures D.all of the above
E.none of the above
42. Bottom-dwelling organisms are termed A.plankton B.nekton C.benthos
43. Which of the following carbonate shelf models would be characterized by a high energy fringe of
bioclastic or oolitic grainstone and a broad expanse of middle shelf grainstone and packstone?
A.drop-off model B.ramp model
44. The most useful exploration technique for finding ancient reefs is A.by well log interpretation
B.by intensive drilling C.by seismic exploration D.all of the above E.none of the above
45. The most important reef types in modern oceans are ? reefs. A.rudist B.coral-algal
C.stromatolitic D.fusulinid E.all of the above are equally important in modern oceans
46. Outer shelf facies are dominated by A.waves B.tides C.density currents D.all of the above
E.none of the above
47. Hydrocarbon reservoirs of peritidal facies are A.typically found in the supratidal facies B.are
characterized by multiple pay zones C.all of the above are true D.none of the above is true
48. Spring tides are times in which the tidal amplitudes are ? than the mean range of tides. A.greater
B.less
49. In fluvial-dominated deltas sediment input tends to be ? than the influence of reworking forces.
A.greater B.less
50. The rate of sedimentation in a distributary mouth bar is probably ? than in any other delta
subenvironment. A.greater B.less
51. Deep marine basins tend to receive sediments primarily by ? sedimentation. A.vertical
B.horizontal C.all of the above are equally important
52. A prograding shelf system would consist of an upward-? sequence. A.fining B.coarsening
53. Trace fossils are typically ? indicators of ecological situations. A.poor B.good
54. The depth of the photic zone usually depends on the amount of ? present. A.water B.salt
C.turbidity D.all of the above E.none of the above
55. If the shelf break is not defined the shelf edge is arbitarily set at a depth of ? meters below sea
level. A.100 B.200 C.300 D.400 E.500
56. ? zones are also referred to as littoral zones. A.supratidal B.subtidal C.intertidal
57. Peritidal environments may be recognized by the A."sandwiching" of the facies between
nonmarine and marine environments B.presence of coarsening-upward sequences
C.predominance of wave-formed structures D.all of the above E.none of the above
58. Deltas A.usually develop where the amount of suspended matter is less than 225 milligrams per
liter B.form in lakes or oceans C.are thick only in cratonic areas with little subsidence D.all of the
above E.none of the above
59. The highest part of a platform margin reef is termed the A.reef flat B.back reef zone C.fore reef
zone D.reef front zone E.reef crest
60. Patch reefs A.often develop behind barriers B.often develop in shelf or lagoon environments
C.may form pinnacles D.may form micro-atolls E.all of the above
61. The thin sheet of water flowing up the beach face is termed A.swash B.surge C.backwash
D.flood tide E.ebb tide
62. Hydrocarbons in wave-dominated systems tend to ?-oriented. A.dip B.strike C.they may be
strike- or dip-oriented
63. The geometry and distribution of sand facies in deltaic systems is influenced by A.sediment input
B.wave energy flux C.tidal energy flux D.all of the above E.none of the above
64. Reefs are often A.good reservoirs B.excellent source rocks for hydrocarbons C.all of the above
D.none of the above
65. ? carbonate shelves are often dominated by muddy, low-energy facies. A.restricted B."open"
66. Which of the following depositional environments would be especially characteristic of fluvialdominated deltas? A.distributary mouth bar B.distributary channel fills C.crevasse splays
D.prodelta and subaqueous delta platform muds and delta plain facies E.all of the above would
be characteristic of fluvial-dominated deltas
67. The reef stage that is characterized by a series of shoals or accumulations of skeletal lime sand is
termed the ? stage. A.Pioneer B.Colonization C.Diversification D.Domination
68. Tidal currents created by rising tides are termed ? currents. A.flood B.ebb C.all of the above
D.none of the above
69. The type of terrigenous shelf system would depend on A.shelf configuration B.tectonics
C.sediment supply D.water circulation E.all of the above
70. Mud facies in terrigenous shelf environments A.may be formed under low energy conditions
B.may form where mud concentration is greater than 100 milligrams per liter C.are typically
bioturbated D.all of the above E.none of the above
71. Estuaries may be formed due to A.sediment loads of more than 160 milligrams per liter
B.subsidence C.small tidal ranges and strong waves D.all of the above E.none of the above
72. Which of the following depositional environments is characterized by stagnant water circulation
due to thresholds composed of till? A.barrier islands B.fjords C.deltas D.estuaries E.peritidal
environments
73. Deep marine sedimentation may form A.oozes B.brown clay and black mud C.iron-rich
sediments D.diagenetic cherts E.all of the above
74. Hydrocarbon reservoirs in deltaic sequences may be entrapped due to A.stratigraphic traps
B.growth faults C.roll-over anticlines D.all of the above E.none of the above
75. Flat or very gently-inclined (less than 1:1000 gradient) surfaces in deep marine basins are termed
A.continental shelves B.continental slopes C.continental rises D.deep sea fans E.abyssal plains
76. Barrier islands are A.separated from the mainland by lagoons or bays B.are built by tides
C.typically finer-grained than backbarrier facies D.all of the above E.none of the above
77. The equilibrium theory explains the characters of A.sediment deposition B.slump features
C.erosional features D.tides E.none of the above
78. A body of cohesionless sediment along a coast that is subject to the effects of breaking waves
forms the A.shoreface B.beach C.barrier D.backbarrier E.peritidal environment
79. The reef stage that typically consists of a limestone lithology and shows the effects of surf is the
A.stabilization B.colonization C.diversification D.domination
80. A delta type that forms an arcuate to cuspate geometry consisting of many coastal beachridge
and barrier sands is A.fluvial-dominated B.tide-dominated C.wave-dominated
81. Estuarine distributary channels A.typically have open or funnel-shaped mouths B.have wide,
sinuous upper reaches C.have tidal ridge facies oriented perpendicular to the channel axis D.all
of the above E.none of the above
82. Trough-crossbedded ridges 65 to 130 feet high that are parallel or oblique to the shoreline are
termed A.sand ridges B.sand waves C.shoestring sands D.sand ribbons E.none of the above
83. Which of the following would not form a potential reservoir derived from carbonate-rich middle
shelf environments? A.shoal sands B.patch reefs C.dolomites D.peritidal evaporites E.leached
horizons beneath unconformities
84. A trough-crossbedded sand and silt shoal formed near the seaward limit of a distributary channel
due to decreasing current velocity is termed a A.distal bar B.bar finger sand C.delta front sheet
sand D.distributary mouth bar E.all of the above
85. Bar finger sands in deltaic environments A.are typically elongate B.are built by deltas depositing
sand bars outward from their mouths C.contain many deformational structures D.all of the above
E.none of the above
86. Topographic features seaward of continental shelf environments which have their lower limits at
500 to 5000 meters below sea level are termed A.continental slopes B.submarine canyons
C.deep sea fans D.continental rises E.deep sea trenches
87. Huge, steep-walled, sinuous, u-shaped valleys that may be hundreds of kilometers long with their
axes sloping seaward as much as 80 meters per kilometers are termed A.deep sea fans B.deep
sea trenches C.submarine canyons D.fjords E.estuaries
88. Which of the following would most likely form a hydrocarbon reservoir associated with reef facies?
A.reef core B.forereef C.reef talus D.all of the above E.none of the above
89. The reef zone developed from the surf zone to a depth of less than 100 meters which is
characterized by encrusting to branching organisms is the ? zone. A.reef crest B.reef front
C.fore reef D.reef flat E.back reef
90. Hydrocarbon reservoirs in deep marine facies may be within A.the foot of deltas B.in faultbounded troughs C.in olistostromes D.in submarine channels, turbidites and fans E.all of the
above
91. Waves along the interface between two water masses of different densities are termed A.turbidity
currents B.contour currents C.internal waves D.tsunamis E.tidal currents
92. A climate in which oceanic water masses are characterized by large temperature variations and in
which winter storms have gale-force winds are A.tropical B.subtropical C.temperate D.subpolar
E.polar
93. A bedded structure built by and from sedentary organisms is termed a A.biostrome
B.stratigraphic reef C.bioherm D.ecologic reef
94. The shape of a delta is controlled by A.coastal morphology B.wave direction and intensity
C.degree of transport by distributaries D.tidal range E.all of the above
95. Subtidal channels A.retain much water at low tide B.are larger than intertidal channels C.are
typically fining-upward sequences D.all of the above E.none of the above
96. Peritidal sediments not deposited in deep channels may be predominated by A.flaser beds
B.lenticular beds C.wavy beds D.all of the above E.none of the above
97. Interchannel deposits between subaqueous fans or cones may consist of A.stratified deposits
B.bioturbated deposits C.graded layers D.pelagic material E.all of the above
98. The widest continental shelves are found along ? plate margins. A.active B.passive
99. In general, deltaic facies ? upward. A.fine B.coarsen
100. The most widespread economic coal facies are in ancient ? environments. A.lagoon B.bay
C.barrier D.deltaic E.estuary
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