Using carbon, hydrogen and helium isotopes to unravel the origin of hydrocarbons in the Wujiaweizi area of the Songliao Basin, China

作者：Jin Zhijun^*; Zhang Liuping; Wang Yang; Cui Yongqiang; Milla Katherine

来源：Episodes, 2009, 32(3): 167-176.

Although abiogenic hydrocarbons have been found in deep-sourced geofluids, they have not been considered a significant source for global hydrocarbon reservoirs. Here, we report a multi-isotopic (C, H and He) study of gases in the Songliao basin in China, revealing the existence of a giant abiogenic hydrocarbon field in the buried volcanoes and clastics overlying volcanies in this rift basin. The progressive carbon isotopic depletion and hydrogen isotopic. enrichment trends for C(1)-C(4) n-alkanes and the strong correlation between the carbon, hydrogen and helium isotopic ratios of gases in the buried volcanoes indicate hydrocarbon production by kinetically-controlled polymerization of methane precursors related to mantle-derived fluids. Given the common occurrence of buried volcanic structures in rift basins, there may exist more abiogenic hydrocarbons associated with buried volcanoes in rift basins that are unrelated to source kitchens than previously thought.

• 出版日期2009-9
• 单位中国科学院地质与地球物理研究所; 中国石油天然气股份有限公司勘探开发研究院; 中国科学院地质与地球物理研究所兰州油气资源研究中心