Their Implication for the Origin of Natural Gas of Feixianguan Formation in Northeastern Sichuan Basin

Key words: 
• solid bitumen in reservoir /
• biomarkers /
• catalytic hydropyrolysis

Abstract: Systemic geochemical analyses such as organic petrology, geochemistry, catalytic hydropyrolysis and GCIRMS show that, the solid bitumen in reservoir of Feixianguan Formation in northeastern Sichuan basin are residuals(pyrobitumen) generated from oil cracking, they have double reflection, high reflection ratio, high S/C and low H/C. Changxing Formation is the primary hydrocarbon source rock for the solid bitumen, while Feixianguan and lower Silurian are the subordination, according to the carbon isotopic compositions of the insoluble constituent and the biomarkers such as sterane and terpane in saturated hydrocarbons of the solvent extracts. There is an obviously genetic relationship between the solid bitumen in Well Po2 of Feixianguan Formation and the kerogen (derived from the hydrocarbon source rock) in Well Guan5 of Feixianguan Formation according to distribution and molecular carbon isotopic compositions of the saturated hydrocarbon of catalytic hydropyrolysis products. Conclusion that the source rock in Feixianguan Formation has contributions to the gas pools of Feixianguan Formation can be acquired.