通过野外地质调查资料及样品测试分析,结合前人研究的结果,对川东南武隆地区五峰组—龙马溪组页岩气形成的基础地质条件进行了研究,指出五峰组与龙马溪组底部富有机质页岩形成于深水陆棚环境,富有机质页岩厚度大,分布广,埋深适中(300~3500 m),脆性矿物含量较高,TOC主要分布于2%~5%之间,热演化程度处于高成熟—过成熟早期阶段,发育溶蚀(微)孔、粒间微孔、粒内微孔、有机质孔及微裂缝等,并通过综合信息叠合分析,提出了5个页岩气富集区.%Based on the outcrop survey, laboratory test of rock samples and previous researches, the conditions of shale gas accumulation in the Upper Ordovician Wufeng Formation and the Lower Silurian Longmaxi Formation in Wulong area of southeast Sichuan Basin were studied in detail. The results indicate that the black shales of Wufeng Formation and the lower Longmaxi Formation are mainly formed in deep shelf sedimentary environment. The organic-rich shale features great thickness, wide distribution, moderate burial depth (0.3~3.5km) and high brittle-mineral content. The TOC values mainly distributed between 2%~5%, and the thermal evolution is at the highly mature stage to early overmature stage. The pore space are solution vugs, intergranular micropores, intragranular micropores, organic pores and microcracks. It is proposed that five zones are the favourable enrichment areas for prospecting of shale gas.
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