石油勘探与开发2025，Vol.52Issue(2)：253-266,14.DOI:10.11698/PED.20240734
四川盆地北部二叠系大隆组页岩气富集高产主控因素及勘探潜力
Controlling factors and exploration potential of shale gas enrichment and high yield in the Permian Dalong Formation,Sichuan Basin,SW China
摘要
Abstract
Based on the basic data of drilling,logging,testing and geological experiments,the geological characteristics of the Permian Dalong Formation marine shales in the Sichuan Basin and the factors controlling shale gas enrichment and high yield are studied.The results are obtained in four aspects.First,the high-quality shale of the Dalong Formation was formed after the deposition of the Permian Wujiaping Formation,and it is developed in the Kaijiang-Liangping trough in the northern part of Sichuan Basin,where deep-water continental shelf facies and deep-water reduction environment with thriving siliceous organisms have formed the black siliceous shale rich in organic matter.Second,the Dalong Formation shale contains both organic and inorganic pores,with stratification of alternated brittle and plastic minerals,which was stacked with severe compaction to enlarge fractures,thereby improving the permeability.In addition to organic pores,a large number of inorganic pores are developed even in ultra-deep(deeper than 4 500 m)layers,contributing a total porosity of more than 5％,which significantly expands the accommodation space for shale gas.Third,the limestone at the roof and floor of the Dalong Formation acted as seal rock in the early burial and hydrocarbon generation stage,providing favorable conditions for the continuous hydrocarbon generation and rich gas preservation in shale interval.In the later reservoir stimulation process,it was beneficial to the lateral extension of the fractures,so as to achieve the optimal stimulation performance and increase the well-controlled resources.Combining the geological,engineering and economic conditions,the favorable area with depth less than 5 500 m is determined to be 1 800 km2,with resources of 5 400× 108 m3.Fourth,the shale reservoirs of the Dalong Formation are thin but rich in shale gas.The syncline zone far away from the main faults in the high and steep tectonic zone,eastern Sichuan Basin,with depth less than 5 500 m,is the most favorable target for producing the Permian shale gas under the current engineering and technical conditions.It mainly includes the Nanya syncline,Tanmuchang syncline and Liangping syncline.关键词
四川盆地/开江—梁平海槽/二叠系/大隆组/硅质页岩/页岩气/富集因素Key words
Sichuan Basin/Kaijiang-Liangping trough/Permian/Dalong Formation/siliceous shale/shale gas/enrichment factor分类
石油、天然气工程引用本文复制引用
雍锐,杨洪志,吴伟,杨雪,杨雨然,黄浩勇..四川盆地北部二叠系大隆组页岩气富集高产主控因素及勘探潜力[J].石油勘探与开发,2025,52(2):253-266,14.基金项目
中国石油天然气股份有限公司科技项目"新区新层系有利区优选与勘探评价关键技术研究"(2023ZZ21YJ04) （2023ZZ21YJ04）
中国石油天然气股份有限公司气藏评价项目"川北地区二叠系海相优质页岩展布规律与储层主控因素研究"(20230304-08) （20230304-08）
