Exploration breakthrough and main controlling factors for shale gas enrichment in the Permian Maokou Formation in Hongxing area in eastern Sichuan Basin
Exploration breakthrough and main controlling factors for shale gas enrichment in the Permian Maokou Formation in Hongxing area in eastern Sichuan Basin
The Permian shale gas in Sichuan Basin shows good hydrocarbon accumulation conditions and exploration potential.After obtaining breakthrough in the Permian Wujiaping Formation,the"high lime content"shale gas in Maokou Formation with a low degree of exploration has been regarded as a major orientation for exploration and replacement The core samples,wireline and mud logging and experimental data in Well HYM-1 are used to systematically analyze the shale gas accumulation conditions and enrichment characteristics in Maokou Formation,and the study results indicate that the shale in the first sub-member of the fourth member of Maokou Formation has the typical geological characteristics of"five highs,one thin and one multiple",i.e.,high carbon content,high lime content,high porosity,high gas content,high Yong's modulus,thin reservoirs,and multiple interbeds;Compared with the shale in Wufeng-Longmaxi Formation,Maokou Formation shale has a higher carbonate mineral content but a lower clay content,and the reservoir space is dominated by organic pores,with few inorganic pores,and an average porosity of 4.27％,showing high porosity as a whole;The average gas content of the first sub-member of the fourth member of Maokou Formation is 4.96m3/t,which shows a high gas content The comprehensive analysis indicates that the development of algal-rich and high-carbon shale,good storage capacity and preservation conditions,as well as the good fracability of shale reservoir are the main controlling factors for the enrichment and high-yield production of shale gas in the fourth member of Maokou Formation.
关键词
四川盆地/川东红星地区/二叠系/茅口组/海相页岩/地质特征/富集控制因素
Key words
Sichuan Basin/Hongxing area in eastern Sichuan Basin/Permian/Maokou Formation/marine shale/geological characteristics/controlling factors for gas enrichment
维普
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