Geochemical and carbon isotopic studies of crude oil destruction, bitumen precipitation, and sulfate reduction in the deep Smackover Formation

Journal Article · Fri Jan 01 04:00:00 EST 1988 · Organic Geochemistry; (UK)

DOI:https://doi.org/10.1016/0146-6380(88)90009-5· OSTI ID:7110477

Sassen, R ^[1]

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1. Louisiana State Univ., Baton Rouge (USA)

Crude oil generated by the Lower Smackover source facies migrated to Upper Smackover reservoirs where slow thermal cracking of crude oil resulted in the formation of gas-condensate and late solid bitumen. Ultimately, only pyrobitumen, methane, and nonhydrocarbon gases including hydrogen sulfide persist in the deepest Smackover reservoirs. The carbon isotopic compositions of crude oils became heavier during crude oil destruction. The carbon isotopic compositions of asphaltenes, NSO-compounds, and saturated hydrocarbons in late solid bitumen and the Lower Smackover source facies became isotopically lighter during crude oil destruction. It is suggested that some isotopically-light components from crude oils were incorporated in late solid bitumen by reactions involving thermochemical sulfate reduction. Thermochemical sulfate reduction and crude oil destruction occurred over a long span of geologic time at temperatures in the 120-150C range.

• OSTI ID: 7110477
• Journal Information: Organic Geochemistry; (UK), Journal Name: Organic Geochemistry; (UK) Vol. 12:4; ISSN ORGED; ISSN 0146-6380
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200 -- Petroleum-- Reserves
Geology
& Exploration
023000* -- Petroleum-- Properties & Composition
ALKANES
ASPHALTENES
ASPHALTS
BITUMENS
CARBON ISOTOPES
CARBONATE ROCKS
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISTRY
CONDENSATES
CRACKING
DECOMPOSITION
DEPOSITION
ENERGY SOURCES
ENVIRONMENTAL TRANSPORT
FLUIDS
FOSSIL FUELS
FUELS
GAS CONDENSATES
GEOCHEMISTRY
GEOLOGIC DEPOSITS
GEOLOGIC HISTORY
GULF COAST
HYDROCARBONS
HYDROGEN COMPOUNDS
HYDROGEN SULFIDES
ISOTOPE RATIO
ISOTOPES
LIQUIDS
MASS TRANSFER
MATURATION
METHANE
MINERAL RESOURCES
NATURAL GAS LIQUIDS
NORTH AMERICA
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PETROLEUM
PETROLEUM DEPOSITS
PYROLYSIS
REDUCTION
RESERVOIR TEMPERATURE
RESOURCES
ROCKS
SEDIMENTARY ROCKS
SOURCE ROCKS
SULFATES
SULFIDES
SULFUR COMPOUNDS
SYNTHESIS
TAR
THERMAL CRACKING
THERMOCHEMICAL PROCESSES
USA