Benayahu, Y., Shlagman, A., and Schleyer, M. H., 2003. Corals of
the South-west Indian Ocean: VI. The Alcyonacea (Octocorallia)
of Mozambique, with a discussion on soft coral distribution on
south equatorial East African reefs. Zoologische Verhandelingen
Leiden, 34, 49–57.
Best, B. A., 1988. Passive suspension feeding in a sea pen: effects
of ambient flow on volume flow rate and filtering efficiency.
Biological Bulletin, 75, 332–342.
Fabricius, K. E., and Alderslade, P., 2001. Soft Corals and Sea
Fans: A comprehensive guide to the tropical shallow water genera of the central-west Pacific, the Indian Ocean and the Red
Sea. Townsville: Australian Institute of Marine Science.
Fabricius, K. E., Alderslade, P., Williams, G., Colin, P., and Golbuu,
Y., 2007. Octocorallia in Palau, Micronesia: effects of biogeography and coastal influences on local and regional biodiversity.
In Kayanne, H., Omori, M., Fabricius, K., Verheij, E., Colin, P.,
Golbuu, Y., and Yurihira, H. (eds.), Coral Reefs of Palau. Palau:
Palau International Coral Reef Centre, pp. 79–91.
Fabricius, K. E., and De’ath, G., 2008. Photosynthetic symbionts
and energy supply determine octocoral biodiversity in coral
reefs. Ecology, 89, 3163–3173.
Fabricius, K. E., Genin, A., and Benayahu, Y., 1995. Flowdependent herbivory and growth in zooxanthellae-free soft
corals. Limnology and Oceanography, 40, 1290–1301.
Fabricius, K. E., and McCorry, D., 2006. Changes in octocoral
communities and benthic cover along a water quality gradient
in the reefs of Hong Kong. Marine Pollution Bulletin, 52,
22–33.
Grasshoff, M., 1999. The shallow water gorgonians of New
Caledonia and adjacent islands (Coelenterata, Octocorallia).
Senckenbergiana Biologica, 78, 1–121.
Hyman, L. H., 1940. The Invertebrates. Protozoa through
Ctenophora. New York: McGraw-Hill.
Ribes, M., Coma, R., Gili, J. M., 1998. Heterotrophic feeding by
gorgonian corals with symbiotic zooxanthellae. Limnology and
Oceanography, 43, 1170–1179.
van Oppen, M. J. H., Mieog, J. C., Sánchez, C. A., and Fabricius,
K. E., 2005. Diversity of algal endosymbionts (zooxanthellae)
in octocorals: the roles of geography and host relationships.
Molecular Ecology, 14, 2403–2417.
Ward, J. R., Kim, K., and Harvell, C. D., 2007. Temperature affects
coral disease resistance and pathogen growth. Marine EcologyProgress Series, 329, 115–121.
Williams, G. C., 1993a. Biotic diversity, biogeography, and phylogeny of pennatulacean octocorals associated with coral reefs in the
Indo-Pacific. Proceedings of the Seventh International Coral
Reef Symposium, 2, 729–735.
Williams, G. C., 1993b. Coral reef octocorals. An Illustrated
Guide to the Soft Corals, Sea Fans and Sea Pens Inhabiting
the Coral Reefs of northern Natal. Durban: Natural Science
Museum, 64 p.
Williams, G. C., 1995. Living genera of sea pens (Coelenterata:
Pennatulacea): illustrated key and synopses. Zoological Journal
of the Linnean Society, 113, 93–140.
Williams, G. C., 1999. Index Pennatulacea: Annotated bibliography
and indexes of the sea pens (coelenterata: Octocorallia) of the
World 1469–1999. Proceedings of the California Academy of
Sciences, 51, 19–103.
Cross-references
Corals: Biology, Skeletal Deposition, and Reef-Building
Corals: Environmental Controls on Growth
Nutrient Pollution/Eutrophication
Reef Interconnectivity/Larval Dispersal
Scleractinia, Evolution and Taxonomy
Sediment Dynamics
Sediments, Properties
Symbiosis; Zooxanthellae
Tropical Cyclone/Hurricane
OIL AND GAS RESERVOIRS AND CORAL REEFS
J. Frederick Sarg
Colorado School of Mines, Golden, CO, USA
Synonyms
Carbonate buildup reservoir; Coral reef reservoir; Reef
buildup reservoir
Definition
Coral reef reservoir: A subsurface volume of coral reef
boundstone and associated skeletal grainsupportstone
(i.e., packstone–grainstone) that has sufficient porosity
and permeability to permit the accumulation of crude oil
or natural gas under adequate trap conditions.
Reservoir characteristics of coral reef systems
Carbonate reservoirs are important contributors to world
oil and gas production and contain more than one-half of
global discovered, recoverable hydrocarbons (Roehl and
Choquette, 1985). Reef and reef-related deposits comprise
a significant proportion of these reservoirs, most prominently in carbonate systems of Siluro-Devonian, Cretaceous, and Neogene age. The Neogene-aged reservoirs
are commonly composed of coral reef and their associated
deposits. In general, the original textures of the carbonate
sediments and their early diagenetic pathways are determinants of the likelihood and extent of carbonate reservoir
rocks. Primary sedimentary textures related to depositional environment, provide the initial matrix pore system
and generally determine the extent of the prospective reservoir. The vast majority of the carbonate reservoirs have
undergone modification of primary pore space because
of syn- to post depositional diagenesis. Both occlusion
and enhancement may occur. Preservation of reservoirquality pore systems is most commonly the result of cessation of occluding processes such as cementation (i.e., early
marine, meteoric phreatic, and/or burial), and compaction,
rather than the result of pore enhancement from processes
like karst solution or dolomitization, although these can be
important processes locally and during certain time
periods (e.g., icehouse times).
Coral reef and related reservoir-prone deposits are most
commonly comprised of thick to massive bedded, reef
boundstones in platform margin and platform interior
patch reef settings and skeletal rudstones, floatstones,
grainstones, and packstones interbedded with the
boundstones and in fore-slope debris. Reef deposits occur
over relatively small areas (square kilometers to 10s of
square kilometers), and range in thickness from meters to
OIL AND GAS RESERVOIRS AND CORAL REEFS
745
the South-west Indian Ocean: VI. The Alcyonacea (Octocorallia)
of Mozambique, with a discussion on soft coral distribution on
south equatorial East African reefs. Zoologische Verhandelingen
Leiden, 34, 49–57.
Best, B. A., 1988. Passive suspension feeding in a sea pen: effects
of ambient flow on volume flow rate and filtering efficiency.
Biological Bulletin, 75, 332–342.
Fabricius, K. E., and Alderslade, P., 2001. Soft Corals and Sea
Fans: A comprehensive guide to the tropical shallow water genera of the central-west Pacific, the Indian Ocean and the Red
Sea. Townsville: Australian Institute of Marine Science.
Fabricius, K. E., Alderslade, P., Williams, G., Colin, P., and Golbuu,
Y., 2007. Octocorallia in Palau, Micronesia: effects of biogeography and coastal influences on local and regional biodiversity.
In Kayanne, H., Omori, M., Fabricius, K., Verheij, E., Colin, P.,
Golbuu, Y., and Yurihira, H. (eds.), Coral Reefs of Palau. Palau:
Palau International Coral Reef Centre, pp. 79–91.
Fabricius, K. E., and De’ath, G., 2008. Photosynthetic symbionts
and energy supply determine octocoral biodiversity in coral
reefs. Ecology, 89, 3163–3173.
Fabricius, K. E., Genin, A., and Benayahu, Y., 1995. Flowdependent herbivory and growth in zooxanthellae-free soft
corals. Limnology and Oceanography, 40, 1290–1301.
Fabricius, K. E., and McCorry, D., 2006. Changes in octocoral
communities and benthic cover along a water quality gradient
in the reefs of Hong Kong. Marine Pollution Bulletin, 52,
22–33.
Grasshoff, M., 1999. The shallow water gorgonians of New
Caledonia and adjacent islands (Coelenterata, Octocorallia).
Senckenbergiana Biologica, 78, 1–121.
Hyman, L. H., 1940. The Invertebrates. Protozoa through
Ctenophora. New York: McGraw-Hill.
Ribes, M., Coma, R., Gili, J. M., 1998. Heterotrophic feeding by
gorgonian corals with symbiotic zooxanthellae. Limnology and
Oceanography, 43, 1170–1179.
van Oppen, M. J. H., Mieog, J. C., Sánchez, C. A., and Fabricius,
K. E., 2005. Diversity of algal endosymbionts (zooxanthellae)
in octocorals: the roles of geography and host relationships.
Molecular Ecology, 14, 2403–2417.
Ward, J. R., Kim, K., and Harvell, C. D., 2007. Temperature affects
coral disease resistance and pathogen growth. Marine EcologyProgress Series, 329, 115–121.
Williams, G. C., 1993a. Biotic diversity, biogeography, and phylogeny of pennatulacean octocorals associated with coral reefs in the
Indo-Pacific. Proceedings of the Seventh International Coral
Reef Symposium, 2, 729–735.
Williams, G. C., 1993b. Coral reef octocorals. An Illustrated
Guide to the Soft Corals, Sea Fans and Sea Pens Inhabiting
the Coral Reefs of northern Natal. Durban: Natural Science
Museum, 64 p.
Williams, G. C., 1995. Living genera of sea pens (Coelenterata:
Pennatulacea): illustrated key and synopses. Zoological Journal
of the Linnean Society, 113, 93–140.
Williams, G. C., 1999. Index Pennatulacea: Annotated bibliography
and indexes of the sea pens (coelenterata: Octocorallia) of the
World 1469–1999. Proceedings of the California Academy of
Sciences, 51, 19–103.
Cross-references
Corals: Biology, Skeletal Deposition, and Reef-Building
Corals: Environmental Controls on Growth
Nutrient Pollution/Eutrophication
Reef Interconnectivity/Larval Dispersal
Scleractinia, Evolution and Taxonomy
Sediment Dynamics
Sediments, Properties
Symbiosis; Zooxanthellae
Tropical Cyclone/Hurricane
OIL AND GAS RESERVOIRS AND CORAL REEFS
J. Frederick Sarg
Colorado School of Mines, Golden, CO, USA
Synonyms
Carbonate buildup reservoir; Coral reef reservoir; Reef
buildup reservoir
Definition
Coral reef reservoir: A subsurface volume of coral reef
boundstone and associated skeletal grainsupportstone
(i.e., packstone–grainstone) that has sufficient porosity
and permeability to permit the accumulation of crude oil
or natural gas under adequate trap conditions.
Reservoir characteristics of coral reef systems
Carbonate reservoirs are important contributors to world
oil and gas production and contain more than one-half of
global discovered, recoverable hydrocarbons (Roehl and
Choquette, 1985). Reef and reef-related deposits comprise
a significant proportion of these reservoirs, most prominently in carbonate systems of Siluro-Devonian, Cretaceous, and Neogene age. The Neogene-aged reservoirs
are commonly composed of coral reef and their associated
deposits. In general, the original textures of the carbonate
sediments and their early diagenetic pathways are determinants of the likelihood and extent of carbonate reservoir
rocks. Primary sedimentary textures related to depositional environment, provide the initial matrix pore system
and generally determine the extent of the prospective reservoir. The vast majority of the carbonate reservoirs have
undergone modification of primary pore space because
of syn- to post depositional diagenesis. Both occlusion
and enhancement may occur. Preservation of reservoirquality pore systems is most commonly the result of cessation of occluding processes such as cementation (i.e., early
marine, meteoric phreatic, and/or burial), and compaction,
rather than the result of pore enhancement from processes
like karst solution or dolomitization, although these can be
important processes locally and during certain time
periods (e.g., icehouse times).
Coral reef and related reservoir-prone deposits are most
commonly comprised of thick to massive bedded, reef
boundstones in platform margin and platform interior
patch reef settings and skeletal rudstones, floatstones,
grainstones, and packstones interbedded with the
boundstones and in fore-slope debris. Reef deposits occur
over relatively small areas (square kilometers to 10s of
square kilometers), and range in thickness from meters to
OIL AND GAS RESERVOIRS AND CORAL REEFS
745