Laboratory Constraints on the Stability of Petroleum at Elevated Temperatures: Implications for the Origin of Natural Gas

Technical Report · Mon Mar 14 00:00:00 EDT 2011

DOI:https://doi.org/10.2172/1008348· OSTI ID:1008348

Seewald, Jeffrey, S.

Results of prior DOE supported research conducted at the Woods Hole Oceanographic Institution have demonstrated the participation of sedimentary minerals and water as reactants and catalysts in chemical transformations associated with the degradation of oil and the formation of low molecular weight organic compounds. The occurrence of such processes in natural environments can be difficult to recognize because the composition of organic alteration products may not be substantially different than those produced by thermal cracking. The goals of this study were the development of diagnostic tools based on hydrogen and carbon isotopes that can be used to identify geochemical processes responsible for the formation of thermogenic natural gas. In addition, our activities were expanded to include experimental investigation of CO2 reduction in aqueous systems at elevated temperature and pressures and an assessment of microbial activity in relatively low temperature (<70°C) natural gas reservoirs in southeastern Oklahoma. Specific objectives included: A laboratory investigation of geochemical processes that regulate the hydrogen isotope composition of low molecular weight hydrocarbons in natural gas at elevated temperatures and pressures. A laboratory investigation of factors that regulate the carbon isotope composition of organic acids in basinal brines. A laboratory assessment of the role of methanol during reduction of CO2 to CH4 under hydrothermal conditions. Characterization of microbial ecosystems in coproduced fluids from the Potato Hills gas field to assess the role of microbes in the generation of natural gas.

• Research Organization: Woods Hole Oceanographic Institution, Woods Hole, MA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: FG02-97ER14746
• OSTI ID: 1008348
• Report Number(s): DOE ER14746 - Final Report; TRN: US201110%%444
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
03 NATURAL GAS
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
58 GEOSCIENCES
BRINES
CARBON ISOTOPES
CATALYSTS
ECOSYSTEMS
HYDROCARBONS
HYDROGEN
HYDROGEN ISOTOPES
METHANOL
MOLECULAR WEIGHT
NATURAL GAS
NATURAL GAS FIELDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORIGIN
PETROLEUM
STABILITY
THERMAL CRACKING
TRANSFORMATIONS
WATER
Natural gas formation
petroleum stability
hydrogen isotopes
carbon isotopes
subsurface biosphere
isotope exchange
microbiology
methane generation
abiotic synthesis
methanol stability.