The origins of petroleum in the northern Gulf of Mexico

Journal Article · Sun Mar 01 00:00:00 EST 1992 · Geochimica et Cosmochimica Acta; (United States)

DOI:https://doi.org/10.1016/0016-7037(92)90061-M· OSTI ID:5059946

Kennicutt, II, M C; McDonald, T J; Comet, P A; Denoux, G J; Brooks, J M ^[1]

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1. Texas A and M Univ., College Station (United States)

The distribution and chemistry of oils in the northern Gulf of Mexico and the adjacent onshore can be explained by multiple sources, facies variations, maturation, and post-generation alteration. Genetic families include Jurassic Smackover, Flexure Trend, Upper Cretaceous, and Paleogene oils. Smackover oils have high sulfur contents, pristane/phytane ratios < 1.0, CPI < 1.0, abundant extended hopanes, C{sub 35}/C{sub 34} hopane ratios {ge} 1.0, and C{sub 30}/C{sub 29} hopane ratios usually {le} 1.0. Flexure Trend oils are similar and contain abundant extended hopanes, high sulfur contents, and V/(Ni + V) > 0.5; these oils are inferred to be sourced in Upper Jurassic/Lower Cretaceous strata. Upper Cretaceous oils contain a distinctive suite of tricyclic and nonhopanoid triterpanes; oleanane is low or absent. Paleogene oils can be recognized by the presence of 18{alpha}(H) oleanane and a lack of extended hopanes. These oils occur from south Texas to southern and offshore Louisiana. Two subfamilies can be recognized based on the relative abundance of triterpanes and steranes. These oils have a presumed Paleogene source. Mixing of oil types is quite prevalent at the geographic boundaries of oil types. The initial control on the distribution of oil and gas in the northern Gulf of Mexico is provided by the areal extent of source rocks. Secondary control is due to Cenozoic deposition, which provides the thermal stress to generate, as well as destroy, oil. Salt tectonics provide conduits for migrating fluids to escape the zone of thermal destruction. Mesozoic source strata again become important in the deep Gulf of Mexico, where Cenozoic sediments thin.

• OSTI ID: 5059946
• Journal Information: Geochimica et Cosmochimica Acta; (United States), Vol. 56:3; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
PETROLEUM
ORIGIN
ALKANES
BIOLOGICAL MARKERS
CARBON 13
DISTRIBUTION
ENVIRONMENTAL TRANSPORT
EXPERIMENTAL DATA
FRACTIONATION
GAS CHROMATOGRAPHY
GAS CONDENSATES
GEOCHEMISTRY
GEOLOGIC FORMATIONS
GEOLOGIC HISTORY
GULF OF MEXICO
ISOTOPE RATIO
MATURATION
MOLECULAR STRUCTURE
NATURAL GAS
NICKEL
OFFSHORE SITES
ONSHORE SITES
PETROLEUM DEPOSITS
SOURCE ROCKS
SULFUR CONTENT
VANADIUM
ATLANTIC OCEAN
CARBON ISOTOPES
CARIBBEAN SEA
CHEMISTRY
CHROMATOGRAPHY
CONDENSATES
DATA
ELEMENTS
ENERGY SOURCES
EVEN-ODD NUCLEI
FLUIDS
FOSSIL FUELS
FUEL GAS
FUELS
GAS FUELS
GASES
GEOLOGIC DEPOSITS
HYDROCARBONS
INFORMATION
ISOTOPES
LIGHT NUCLEI
LIQUIDS
MASS TRANSFER
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NATURAL GAS LIQUIDS
NUCLEI
NUMERICAL DATA
ORGANIC COMPOUNDS
RESOURCES
SEAS
SEPARATION PROCESSES
STABLE ISOTOPES
SURFACE WATERS
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020200* - Petroleum- Reserves
Geology
&amp; Exploration