川东北地区埋藏史及热史分析——以普光2井为例

Burial and thermal histories of northeastern Sichuan Basin：A case study of well Puguang 2

吴群 彭金宁

Wu Qun Peng Jinning

西北大学 地质系, 西安 710069 2. 中国石油化工股份有限公司 华东分公司, 南京 210011 3. 中国石油化工股份有限公司 石油勘探开发研究院 无锡石油地质研究所, 江苏 无锡 214126

Department of Geology, Northwest University, Xi'an, Shaanxi 710069, China 2. SINOPEC East China Company, Nanjing, Jiangsu 210011, China 3. Wuxi Research Institute of Petroleum Geology, SINOPEC, Wuxi, Jiangsu 214126, China

基于前人研究资料,运用热成熟度指数法(TTI),以普光2井为例,恢复了川东北地区地热史和地层埋藏史,探讨了研究区烃源岩的热演化和生排烃过程。研究认为:各烃源层的成熟度演化主要定型于白垩纪末期,下寒武统烃源岩生烃期局限在晚二叠世—晚三叠世;上奥陶统至下志留统烃源岩的快速生烃期为中三叠世—晚三叠世和中侏罗世;二叠系烃源岩的快速生烃期为晚三叠世和中侏罗世。另外,各烃源岩都经历了至少2次生烃高峰期,包括成熟期的生油(液态烃)高峰期及高成熟期的尚未排除的残留液态烃进一步裂解生气高峰期。

The thermal maturity index (TTI) was applied in well Puguang 2 to recover the burial and thermal histories of the northeastern Sichuan Basin. In this way, the thermal evolution of source rocks and the hydrocarbon generation and migration processes in the study area were discussed. The maturity of source rocks evolved until the end of Cretaceous. Source rocks in the Lower Cambrian gave birth to hydrocarbon only from the Late Permian to the Late Triassic. Source rocks from the Upper Ordovician to the Lower Silurian gave birth to hydrocarbon rapidly from the Middle Triassic to the Late Triassic and also during the Middle Jurassic. Source rocks in Permian gave birth to hydrocarbon rapidly during the Late Triassic and the Middle Jurassic. All the above-mentioned source rocks experienced at least 2 hydrocarbon generation peaks, including the oil (liquid hydrocarbon) generation during the mature stage and the cracking of liquid hydrocarbon to gas during the high-mature stage.

中国石化科技部项目"四川盆地二叠系烃源岩及其资源潜力研究"(P08007)资助

https://doi.org/10.11781/sysydz201302133