Geologic Exploration

Reservoir characteristics of organic-rich shale gas in the Longmaxi Formation, Weiyuan Area,and their influence on gas content

  • LIU Yi ,
  • LI Yizhen ,
  • HAO Yuexiang ,
  • JIANG Yumeng ,
  • CHEN Xue
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  • Shale Gas Exploration and Development Project Management Department,CNPC Chuanqing Drilling Engineering Co.,Ltd.,Chengdu,Sichuan 610051,China

Received date: 2025-05-19

  Revised date: 2026-01-04

  Online published: 2026-09-04

Abstract

Shale gas reservoirs in the Longmaxi Formation of the Weiyuan Area show significant single-well productivity differences,and the main controlling factors affecting gas content remain unclear,constraining effective exploration and development of shale gas in this area.Therefore,organic-riched shale reservoirs of the Long 1-1 submember in the Longmaxi Formation of the Weiyuan Area were investigated.By integrating X-ray diffraction(XRD) mineral analysis,organic geochemical tests,SEM observations,and rock petrophysical tests,the basic characteristics of shale gas reservoirs were systematically analyzed,and their controlling effects on gas content were discussed.The results show that shale reservoirs of the Long 1-1 submember have relatively high quartz content,total organic carbon(TOC) content and thermal maturity.The storage space is dominated by organic-matter pores,and both porosity and gas content are relatively high,indicating good resource potential.Shale gas-bearing properties are jointly controlled by material basis,storage space and preservation conditions.High TOC content,large effective reservoir thickness,high brittle-mineral content and a well-developed pore system provide favorable conditions for shale gas generation and storage,whereas strong sealing capacity of roof and floor and a high formation pressure coefficient are key to shale gas enrichment and preservation.Hydrocarbon expulsion in the study area is relatively weak,leading to high present-day residual gas content;moreover,shale gas wells in synclinal structural zones generally have higher production than those in anticlinal structural zones.The results provide a geological basis for favorable area selection and efficient development of shale gas reservoirs in the Longmaxi Formation.

Cite this article

LIU Yi , LI Yizhen , HAO Yuexiang , JIANG Yumeng , CHEN Xue . Reservoir characteristics of organic-rich shale gas in the Longmaxi Formation, Weiyuan Area,and their influence on gas content[J]. Special Oil & Gas Reservoirs, 2026 , 33(3) : 34 -43 . DOI: 10.3969/j.issn.1006-6535.2026.03.004

References

[1] CURTIS J B.Fractured shale-gas systems[J].AAPG Bulletin,2002,86(11):1921-1938.
[2] 周文,蒋柯,徐浩,等.从页岩到页岩气储层:论泥(页)岩层构成油气储集层的必要条件[J].成都理工大学学报(自然科学版),2025,52(1):140-152.
ZHOU Wen,JIANG Ke,XU Hao,et al.From shale to shale gas reservoir:on the necessary conditions for a shale layer to form an oil or gas reservoir[J].Journal of Chengdu University of Technology(Science & Technology Edition),2025,52(1):140-152.
[3] 郭旭升,腾格尔,魏祥峰,等.四川盆地深层海相页岩气赋存机理与勘探潜力[J].石油学报,2022,43(4):453-468.
GUO Xusheng,BORJIGIN Tenger,WEI Xiangfeng,et al.Occurrence mechanism and exploration potential of deep marine shale gas in Sichuan Basin[J].Acta Petrolei Sinica,2022,43(4):453-468.
[4] 邓乃尔,徐浩,周文,等.基于深度学习的岩石矿物智能识别研究进展与发展趋势[J].成都理工大学学报(自然科学版),2025,52(1):64-93.
DENG Naier,XU Hao,ZHOU Wen,et al.Research progress and development trends of intelligent recognition of rock minerals based on deep learning[J].Journal of Chengdu University of Technology(Science & Technology Edition),2025,52(1):64-93.
[5] 龙虹宇,张亚,和源,等.川中古隆起北斜坡下寒武统沧浪铺组一段混合沉积特征及模式[J].东北石油大学学报,2025,49(2):19-29.
LONG Hongyu,ZHANG Ya,HE Yuan,et al.Mixed sedimentary characteristics and sedimentary models of the first member of Lower Cambrian Canglangpu Formation in the northern slope area of the central Sichuan Paleo-uplift[J].Journal of Northeast Petroleum University,2025,49(2):19-29.
[6] 张金川,聂海宽,徐波,等.四川盆地页岩气成藏地质条件[J].天然气工业,2008,28(2):151-156.
ZHANG Jinchuan,NIE Haikuan,XU Bo,et al.Geological condition of shale gas accumulation in Sichuan Basin[J].Natural Gas Industry,2008,28(2):151-156.
[7] LOUCKS R G,REED R M,RUPPEL S C,et al.Spectrum of pore types and networks in mudrocks and a descriptive classification for matrix-related mudrock pores[J].AAPG Bulletin,2012,96(6):1071-1098.
[8] 张金川,刘树根,魏晓亮,等.页岩含气量评价方法[J].石油与天然气地质,2021,42(1):28-40.
ZHANG Jinchuan,LIU Shugen,WEI Xiaoliang,et al.Evaluation of gas content in shale[J].Oil & Gas Geology,2021,42(1):28-40.
[9] 金之钧,胡宗全,高波,等.川东南地区五峰组—龙马溪组页岩气富集与高产控制因素[J].地学前缘,2016,23(1):1-10.
JIN Zhijun,HU Zongquan,GAO Bo,et al.Controlling factors on the enrichment and high productivity of shale gas in the Wufeng-Longmaxi Formations,southeastern Sichuan Basin[J].Earth Science Frontiers,2016,23(1):1-10.
[10] 周志军,张国青,崔春雪,等.页岩储层孔隙结构表征及物性下限确定方法及应用[J].特种油气藏,2024,31(4):96-102.
ZHOU Zhijun,ZHANG Guoqing,CUI Chunxue,et al.Methods and applications for characterizing pore structure and determining physical property lower limit in shale reservoirs[J].Special Oil & Gas Reservoirs,2024,31(4):96-102.
[11] 王淑芳,董大忠,王玉满,等.四川盆地志留系龙马溪组富气页岩地球化学特征及沉积环境[J].矿物岩石地球化学通报,2015,34(6):1203-1212.
WANG Shufang,DONG Dazhong,WANG Yuman,et al.Geochemical characteristics the sedimentation environment of the gas-enriched shale in the Silurian Longmaxi Formation in the Sichuan Basin[J].Bulletin of Mineralogy,Petrology and Geochemistry,2015,34(6):1203-1212.
[12] 周文,王浩,谢润成,等.中上扬子地区下古生界海相页岩气储层特征及勘探潜力[J].成都理工大学学报(自然科学版),2013,40(5):569-576.
ZHOU Wen,WANG Hao,XIE Runcheng,et al.Characteristics and exploration potential of Lower Paleozoic marine shale gas reservoir in middle-upper Yangtze Area,China[J].Journal of Chengdu University of Technology(Science & Technology Edition),2013,40(5):569-576.
[13] 刘树根,曾祥亮,黄文明,等.四川盆地页岩气藏和连续型-非连续型气藏基本特征[J].成都理工大学学报(自然科学版),2009,36(6):578-592.
LIU Shugen,ZENG Xiangliang,HUANG Wenming,et al.Basic characteristics of shale and continuous-discontinuous transition gas reservoirs in Sichuan Basin,China[J].Journal of Chengdu University of Technology(Science & Technology Edition),2009,36(6):578-592.
[14] 梅庆华.四川盆地乐山—龙女寺古隆起构造演化及其成因机制[D].北京:中国地质大学(北京),2015.
MEI Qinghua.Tectonic evolution and formation mechanism of Leshan-Longnyusi Paleo-uplift,Sichuan Basin[D].Beijing:China University of Geosciences (Beijing),2015.
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