A chemical kinetic model of hydrocarbon generation from the Bakken Formation, Williston Basin, North Dakota

Technical Report · Thu Oct 01 04:00:00 EDT 1992

OSTI ID:7027063

Sweeney, J J; Braun, R L; Burnham, A K ^[1]; Gosnold, W D ^[2]

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1. Lawrence Livermore National Lab., CA (United States)
2. North Dakota Univ., Grand Forks, ND (United States)

This report describes a model of hydrocarbon generation and expulsion in the North Dakota portion of the Williston Basin. The modeling incorporates kinetic methods to simulate chemical reactions and 1-dimensional conductive heat flow models to simulate thermal histories of the Mississippian-Devonian Bakken Formation source rock. We developed thermal histories of the source rock for 53 wells in the basin using stratigraphic and heat flow data obtained by the University of North Dakota. Chemical kinetics for hydrocarbon generation, determined from Pyromat pyrolysis, were, then used with the diennal histories to calculate the present day value of the Rock-Eval T[sub max] for each well. The calculated Rock-Eval T[sub max] values agreed with measured values within amounts attributable to uncertainties in the chemical kinetics and the heat flow. These optimized thermal histories were then used with a more detailed chemical kinetic model of hydrocarbon generation and expulsion, modified from a model developed for the Cretaceous La Luna shale, to simulate pore pressure development and detailed aspects of the hydrocarbon chemistry. When compared to values estimated from sonic logs, the pore pressure calculation underestimates the role of hydrocarbon generation and overestimates the role of compaction disequilibrium, but it matches well the general areal extent of pore pressures of 0.7 times lithostatic and higher. The simulated chemistry agrees very well with measured values of HI, PI, H/C atomic ratio of the kerogen, and Rock-Eval S1. The model is not as successful in simulating the amount of extracted bitumen and its saturate content, suggesting that detailed hydrous pyrolysis experiments will probably be needed to further refine the chemical model.

• Research Organization: Lawrence Livermore National Lab., CA (United States)
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 7027063
• Report Number(s): UCRL-ID-112038; ON: DE93003335
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
04 OIL SHALES AND TAR SANDS
040200 -- Oil Shales & Tar Sands-- Reserves
Geology
& Exploration
BITUMINOUS MATERIALS
CARBONACEOUS MATERIALS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DECOMPOSITION
DEVELOPED COUNTRIES
FEDERAL REGION VIII
GEOLOGY
HEAT FLOW
HYDROCARBONS
KEROGEN
KINETICS
MATERIALS
MATTER
MATURATION
MIGRATION
NORTH AMERICA
NORTH DAKOTA
ORGANIC COMPOUNDS
ORGANIC MATTER
PETROLEUM GEOLOGY
PORE PRESSURE
PYROLYSIS
REACTION KINETICS
SOURCE ROCKS
STRATIGRAPHY
THERMOCHEMICAL PROCESSES
USA