Characteristics of Organic Geochemistry of Lucaogou Formation Source Rocks, Upper Permian, Santanghu Basin

Key words: 
• Lucaogou Formation /
• source rock /
• geochemical characteristics /
• carbonyl compounds /
• hydrocarbon generation /
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Abstract: Upper Permian Lucaogou Formation of Santanghu Basin with a wide distribution, large thickness, high organic carbon content, and good hydrocarbon potential, was the main source rocks in the basin. Soluble organic matter from rock samples contains rich carbonyl compounds such as fatty acids, fatty acid esters, etc. Saturated hydrocarbons and aromatics content increasing along with the depth increase, but nonhydrocarbon content and organic carbon decreasing, showed these carbonyl compounds in the source rocks have made a greater contribution to hydrocarbon generation. The indicators of saturated hydrocarbon showed that the depositional environment of source rocks was the salinity lake, reduction conditions. The input of the parent material dominated by aquatic organisms, terrestrial input less. A lot of evidence indicated that bacteria entered the organic matter deposition during the early diagenesis stages and formed part of the original organic matter; bacteria transformed the original organic matter and produced the aforementioned carbonyl compounds, hydrocarbons could be generated in the thermal effect and affection of microorganisms.