Geochemistry and Origins of Reservoir Solid Bitumen in the Northeast Sichuan Basin, SW China
Mail Box 296#, Geochemistry Laboratory, Faculty of Natural Resources & Information Technology,
China University of Petroleum Changping, Beijing, China, 102249.
Sichuan Basin is one of the largest natural gas provinces in China. Gas accumulations with reservoir solid bitumen occurred in Carboniferous, Permian and Triassic strata in the Northeast Sichuan Basin, SW China. Two types of gas accumulations (thermal cracking gas and sour gas) were identified in this basin. Consequently, reservoir solid bitumen may be formed by thermal alteration or thermochemical sulfate reduction of hydrocarbons. The main goal of this project is to investigate the geochemical characteristics and the origins of bitumen in the basin.
The main methods and techniques of the research are as follows:
1. Performing microscopic observations of reservoir bitumen with optical microscope, and measuring vitrinite reflectance and bitumen reflectance.
2. Extracting soluble organic matter from reservoir bitumen, then isolating the aliphatic, aromatic, polar NSO and asphaltene fractions. Utilizing for generation bound biomarkers from the originally insoluble reservoir bitumen via catalytic hydropyrolysis. Analyzing the yields of the aliphatics and aromatics released from hydropyrolysis to assess the maturity, sedimentary environment and biogenic sources of bitumen. Biomarkers and stable carbon isotopes of the aliphatics and aromatics were analyzed by gas chromatography-mass spectrometry and isotope ratio mass-spectrometer, respectively.
3. Studying the characteristics of biomarkers of reservoir bitumen to differentiate bitumen formed by thermal cracking and thermochemical sulfate reduction and discussing the significance of reservoir bitumen in petroleum accumulation.
This project will be helpful to understand thermal evolution and origins of reservoir solid bitumen and will guide natural gas exploration in Sichuan Basin.
AAPG Search and Discovery Article #90070 © 2007 AAPG Foundation Grants in Aid