Geology Reference
In-Depth Information
Duke, W.L. (1985): Hummocky cross stratification: tropical
hurricanes, and intense winter storms. - Sedimentology,
32 , 167-194
Gischler, E. (1995): Current and wind induced facies pat-
terns in a Devonian atoll: Iberg reef, Harz Mts., Germany.
- Palaios, 10 , 180-189
Harms, J.C., Southard, J.B., Spearing, D.R., Walker, R.G.
(1975): Depositional environments as interpreted from pri-
mary sedimentary structures and stratification sequences.
- Society of Economic Paleontologists and Mineralogists,
Short Course, 2 , 161 pp.
Hubbard, D.K. (1992): Hurricane-induced sediment transport
in open-shelf tropical systems - an example from St.Croix,
U.S. Virgin Islands. - J. Sed. Petrol., 62 , 946-960
Hughes, T. (ed., 1993): Special issue: Disturbance: effects on
coral reef dynamics. - Coral Reefs, 12 , 117-233
Ito, M., Ishigaki, A., Nihikawa, T., Saito, T.: (2001): Tempo-
ral variations in the wave lengths of hummocky cross-
stratification. Implications for storm intensity through
Mesozoic and Cenozoic. - Geology, 29 , 87-89
Myrow, P.M., Southard, J.B. (1996): Tempestite deposition.
- Journal of Sedimentary Research, A, 66 , 875-887
Nummedal, D. (1991): Shallow marine storm sedimentation
- the oceanographic perspective. - In: Einsele, G., Riecken,
W., Seilacher, A. (eds.): Cycles and events in stratigraphy.
- 227-248, Berlin (Springer)
Pielke, R.A. (1990): The hurricane. - 228 pp., London
(Routledge)
Rogers, C.S. (1993): Hurricanes and coral reefs: the interme-
diate disturbance hypothesis revisited. - Coral Reefs, 12 ,
127-137
Scoffin, T.P. (1993): The geological effects of hurricanes on
coral reefs and the interpretation of storm deposits. - Coral
Reefs, 12 , 203-221
Seilacher, A., Aigner, T. (1991): Storm deposits at the bed,
facies, and basin scale: the geologic perspective. - In:
Einsele, G., Riecken, W., Seilacher, A. (eds.): Cycles and
events in stratigraphy. - 227-248, Berlin (Springer)
Shinn, E.A., Steinen, R.P., Dill, R.F., Major, R. (1993): Lime-
mud layers in high-energy tidal channels: a record of hur-
ricane deposition. - Geology, 21 , 603-605
Further reading: K032, K165
Box 12.4. Diagnostic features of storm effects on an-
cient reefs. Criteria that have also become evident in the
Cozumel study are marked by an asterisk.
Reef detritus
• Fore-reef detritus: Extended slopes and aprons con-
sisting predominantly of reef-derived material are
valuable indicators of storm effects on reefs growing
in shallow waters. The limestones are breccias, rud-
stones or floatstones. Angular and rounded clasts are
intermixed with isolated fossils. Marked differences
in the microfacies of the clasts are due to different
source areas of the eroded material.
• Reef breccias, rudstones and floatstones deposited in
near-coast position (*).
• Large, variously sized coral blocks or reef blocks oc-
curring within fine-grained lagoonal sediments (*).
• Accumulation of fragments of corals or other reef-
builders acting as a base for encrusting organisms (*).
Compositional biotic changes
• Striking vertical and lateral differences of paleonto-
logical criteria on a decimeter or meter scale.
• Conspicuous reduction of branching growth forms
in favor of massive growth forms (*).
• High-growing reefbuilders followed by a level of low-
growing reefbuilders along a conspicuous boundary.
• Abrupt differences in the taxonomic composition and
frequency of reefbuilder associations (*).
Discontinuities and textural changes
Discontinuity planes and fissures disrupting the reef
structure.
Beds with abundant, poorly sorted coral debris over-
lain by microbial carbonates (*).
Conspicuous changes in the composition and grain
size of the sediment deposited between and within
reefbuilders (*).
Fine-grained fossil-free layers that may correspond
to carbonate mud settled down after the abatement of
storms.
Layers or lenses with high organic content can be
caused by accumulation of destroyed plants.
induced porous skeletal sand waves over dense mound
facies can form hydrocarbon traps, as shown by hydro-
carbon reservoirs in capping beds of Carboniferous
Waulsortian mounds.
12.1.3 Marine Carbonate Substrates
The composition and type of carbonate substrates de-
pend on depositional, biological and diagenetic factors.
The substrate type affects feeding modes as well as the
penetration and attachment of benthic organisms. Lime-
stones represent former soft substrates and former hard
substrates and various modifications of these two ba-
sic categories . Soft bottoms consist of loose grains ex-
hibiting different consistencies depending on the grain
size and water content. Hard bottoms are immobile sub-
strates that are firm or hard enough to take encrusting
and boring organisms (Sect. 5.2.4.1 and Sect. 9.2). They
represent a non-depositional surface and are resistant
to submarine erosion. Differences in the states of con-
Basics: Storms
Aigner, T. (1985): Storm depositional systems. - Lecture Notes
in Earth-Science, 3 , 174 pp., Stuttgart (Schweizerbart)
Barron, E.C. (1989): Severe storms during earth history. -
Geological Society of America, Bulletin, 101 , 601-612
Bourrouilh-Le Jan, F.G. (1998): The role of high-energy
events (hurricanes and/or tsunamis) in the sedimentation,
diagenesis and karst initiation of tropical shallow water
carbonate platforms and atolls. - Sedimentary Geology,
118 , 3-36
Dott, R.H., Bourgeois, J. (1982): Hummocky stratification:
significance of variable bedding sequences. - Geological
Society of America, Bulletin, 93 , 663-680
 
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