Characteristics of Gray Source Rock Gas Reservoirs in The First Member of Maokou Formation in Southeastern Sichuan

Zhendong Wang; Xu Wang; Ruijiao Zhang; Linjie Li

doi:10.6911/WSRJ.202502_11(2).0008

Authors

Zhendong Wang
Xu Wang
Ruijiao Zhang
Linjie Li

DOI:

https://doi.org/10.6911/WSRJ.202502_11(2).0008

Keywords:

Southeast Sichuan basin; First member of Maokou formation; Grey source rock gas; Reservoir characteristics.

Abstract

The gray source rock gas reservoir in the first member of the Middle Permian Maokou Formation in southeastern Sichuan has unique geological characteristics and is an important unconventional natural gas reservoir. Through the observation of rock slices and scanning electron microscopy and the analysis and processing of existing sample data, the reservoir characteristics of the first member of Maokou Formation are clarified, and the reservoir evaluation system and evaluation of the first member of Maokou Formation are established based on its characteristics. The results show that the first member of Maokou Formation mainly develops a set of tight limestone source rock reservoirs with low porosity and low permeability, which are mainly composed of limestone and bioclastic micrite. The reservoir space is dominated by micro-fractures and inorganic pores, with a small amount of organic pores. The pore morphology of the reservoir is complex and changeable. It is filled with clay minerals, calcite and talc. Micropores, mesopores and macropores are developed, and the pore size is mainly distributed in 1.5 nm to 60.4 nm. There is a certain positive correlation between total organic carbon ( TOC ) and porosity. At the same time, the geographical distribution trend of TOC content in limestone source rocks is consistent with the distribution trend of porosity, which shows a gradual increase from northwest to southeast.

Downloads

Download data is not yet available.

References

[1] Xu Zuxin. Genesis and Source of Gas in Middle Permian Maokou Formation of Eastern Sichuan Basin[J]. Special Oil & Gas Reservoirs, 2019, 26(02): 16-22.

[2] Hu Anping, Pan Liyin, Hao Yi, et al. Origin, Characteristics and Distribution of Dolostone Reservoir in Qixia Formation and Maokou Formation, Sichuan Basin, China[J]. Marine Origin Petroleum Geology, 2018, 23(02): 39-52.

[3] Jiang Qingchun, Wang Zecheng, Wu Wang, et al. Accumulation conditions and favorable exploration orientation of unconventional natural gas in the marl source rock of the first member of the Middle Permian Maokou Formation, Sichuan Basin[J]. China Petroleum Exploration, 2021, 26(06): 82-97.

[4] Zhang Jinchuan, Nie Haikuan, Xu Bo, et al. Geological condition of shale gas accumulation in sichuan basin[J]. Natural Gas Industry, 2008, 28(02): 151-156.

[5] Dong Dazhong, Gao Shikui, Huang Jinliang, et al. A discussion on the shale gas exploration &development prospect in the Sichuan Basin[J]. Natural Gas Industry, 2014, 34(12): 1-15.

[6] Xiao Di, Tan Xiucheng, Shan Shujiao, et al. The Restoration of Palaeokarst Geomorphology of Middle Permian Maokou Formation and its Petroleum Geological Significance in Southern Sichuan Basin[J]. Acta Geologica Sinica, 2014, 88(10): 1992-2002.

[7] Li Shan. The Distribution of Source Rocks and Hydrocarbon Accumulation Model of the Permian Maokou Formation in Sichuan Basin[D]. China University of Petroleum (Beijing), 2021.

[8] Jiang Weiwei, Liu Yihe, Hao Tianyao et al. Comprehensive study of geology and geophysics of sichuan basin[J]. Progress in Geophysics, 2001, 16(01): 11-23.

[9] Jiang Qingchun,Wang Weiming,and Lyu Qixia."Characteristics and Controlling Factors of Tight Marl Reservoirs with an Eyelid-Shaped Structure of the First Member of the Deep Maokou Formation in Eastern Sichuan."Energies 16.5(2023):2353-2353.

[10] Han Yueqing, Li Shuangjian, Han Wenbiao, et al. Pore characteristics of marl reservoir in Maokou Formation of Middle Permian, southeastern Sichuan Basin[J]. Petroleum Geology & Experiment, 2022, 44(04): 666-676.

[11] Zhang Tingshan, Chen Xiaohui, Liu Zhicheng, et al. Effect of Emeishan Mantle Plume over the Sedimentary Pattern of Mid-Permian Xixia Period in Sichuan Basin[J]. Acta Geologica Sinica, 2011, 85(8): 1251-1264.

[12] Wang Xinxin. Sedimentological research on the carbonate reservoir of Chihsia and Maokou formation in Northwest Sichuan[D]. Chengdu University Of Technology, 2017.

[13] Hu Dongfeng, Wang Liangjun, Zhang Hanrong, et al. Discovery of carbonate source rock gas reservoir and its petroleum geological implications: A case study of the gas reservoir in the first Member of Middle Permian Maokou Formation in the Fuling area, Sichuan Basin. Natural Gas Industry[J]. 2020, 40(07): 23-33.

[14] Liang Xing, Xu Zhengyu, Li Weimin, et al. Characteristics and main controlling factors of the limy source rock gas reservoir in the first member of the Lower Permian Maokou Formation in the southern Sichuan and western Chongqing area: a case study of well DB 1[J]. Petroleum Geology & Experiment. 2023, 4(45): 1-12.

[15] Wang Ying."Reservoir characteristics of the second member in Maokou Formation, Middle Permian, northeast Sichuan Basin".Ed.Daqing Oilfield Co.,Ltd. (China),2023.