Distribution and Geochemical Significance of Rearranged Hopanes in Jurassic Source Rocks and Related Oils in the Center of the Sichuan Basin, China
Xiaolin Lu, Meijun Li, Xiaojuan Wang, Tengqiang Wei, Youjun Tang, Haitao Hong, Changjiang Wu, Xiaoyong Yang, Yuan Liu
Abstract
). The results of this study show that the relatively high abundance of rearranged hopanes in Jurassic source rocks in the study area is associated with their depositional environments and with clay-mediated acidic catalysis rather than, as was previously thought, thermal maturity. Shallow lacustrine facies with brackish water and a suboxic to weak reducing sedimentary environment have contributed to the enrichment of rearranged hopanes, and clay-mediated acidic catalysis may also have had a positive influence on their abundance. The distribution patterns of the diahopane series indicate that the oils from Jurassic reservoirs in the Gongshanmiao Oilfield are sourced from Jurassic source rocks. Rearranged hopanes are therefore considered to be effective biomarkers for oil-source correlation in the center of the Sichuan Basin.