Formation and Distribution of Tight Sand Gas Reservoirs in the Sichuan Basin, China

WANG Hongjun, BIAN Congsheng, XU Zhaohui, WANG Zecheng, LI Yongxin


Located in the central west of China, the Sichuan Basin is abundant in natural gas resources. It is the earliest basin where natural gas was discovered and utilized in the world. After more than 60 years’ exploration, many gas fields have been found in the Paleozoic - Mesozoic carbonate and clastic formations. The basin has become a critical production base in China for its cumulative proved recoverable gas reserves of more than 8000×108 m3, and gas production over 150×108 m3 in 2010. During the past decade, many tight gas reservoirs have been found in the Xujiahe coal measures of the upper Triassic continental deposits. Based on lithology, this suite of formation can be divided into six members from bottom to top. The source rocks are the coal beds and carbon-bearing mudstones in Xu1, Xu3 and Xu5 members with relatively high organic carbon contents and type III kerogen; the reservoir rocks are the tight sandstones in Xu2, Xu4 and Xu6 members. The source rocks and the reservoirs distribute alternatively and widely in “sandwiched” structure, providing favorable conditions for natural gas accumulating near source. As the formations are gentle and lack of structural traps, the lithologic gas reservoirs dominate the Xujiahe tight sandstones. Both coal-measure source rocks and sandstone reservoir distribute in strong heterogeneity, leading to thin gas-layers in the reservoir, poor continuity in plane, and varying full-up ratio and gas saturation in the gas reservoir. Within the 80,000 km2 area, the Xujiahe Formation has the features of widespread gas-bearing beds and local gas enrichment. The current high-yield gas wells are mainly distributed in the tectonic highs or fractured zones in the areas with effective source-reservoir assemblages. The resources assessment is made considering the tight gas accumulating intensively into reservoir. It reveals the favorable gas-bearing area up to 6-7×104 km2 and the estimated recoverable gas reserves of 2-3×1012 m3 in the Xujiahe Formation.

Key words: Sichuan Basin; Tight sandstone; Coal measures; Tight gas; “Sandwiched” structure; Resources


Sichuan Basin; Tight sandstone; Coal measures; Tight gas; “Sandwiched” structure; Resources

Full Text:



[1] Liu, D. L., Song, Y., & Xue, A. M. (2000). Comprehensive study on the structures and natural gas accumulation zones in the Sichuan Basin. Beijing: Petroleum Industry Press.

[2] Dai, J. X., Zou, C. N., & Tao, S. Z. (2007). Formation conditions and main controlling factors of large gas fields in China. Natural Gas Geoscience, 18(4), 17-29.

[3] Zhao, W. Z., Bian, C. S., & Xu, C. C. (2011). Assessment on gas accumulation potential and plays within the Xu1, Xu3 and Xu5 Members in Sichuan Basin. Petroleum Exploration and Development, 36(4), 548-555.

[4] Zhao, W. Z., Wang, H. J., & Xu, C. C. (2010). Reservoir-forming mechanism and enrichment conditions of the extensive Xujiahe Formation gas reservoirs, central Sichuan Basin. Petroleum Exploration and Development, 37(2), 1-12.

[5] Zhao, W. Z., Wang, Z. C., & Wang, H. J. (2008). Principal characteristics and forming conditions for medium-low abundance large scale oil/gas fields in China. Petroleum Exploration and Development, 35(9), 641-650.

[6] Zhai, G. M. et al., (1989). Petroleum geology of China (p. 10). Beijing: Petroleum Industry Express.

[7] Deng, K. L. (1996). Evolution and petroleum exploration in the Sichuan Basin. Natural Gas Industry, 12(5), 7-13.

[8] Luo, Q. H., & Wang, S. Q. (1996). Study on natural gas enriching conditions of the Triassic gas-bearing series in the central and western Sichuan Basin. Natural Gas Industry, 12(6), 40-55.

[9] Nelson, P. H. (2009). Pore-throat sizes in sandstones, tight sandstones, and shales. AAPG Bulletin, 93(3), 329-340.

[10] Riedel, M., & Rohr, K. M. M. (2012). Gas hydrate within the Winona Basin, offshore western Canada. Marine and Petroleum Geology, 30(1), 66-80.

[11] Liu, S. G., Tong, C. G., & Luo, Z. L. (1995). Formation and evolution of the later Triassic foreland basin in the western Sichuan Basin. Natural Gas Industry, 15(2), 11-14.

[12] Adedosu, T. A., Sonibare, O. O., Tuo, J. C., & Ekundayo, O. (2012). Biomarkers, carbon isotopic composition and source rock potentials of Awgu coals, middle Benue trough, Nigeria. Journal of African Earth Sciences, 66/67, 13-21.

[13] Adekola, S. A., & Akinlua, A. (2012). Source rock characterization within the stratigraphic settings of the orange basin, South Africa. Petroleum Science and Technology, 30(6), 545-558.

[14] Hammad, M. M., & El Nady, M. M. (2012). Oil-source rocks correlation based on the biomarker distribution of EWD and Qarun Oilfields, North Western Desert. Egypt Petroleum Science and Technology, 30(2), 133-146.

[15] Aali, J., Rahmani, O. (2012). H2S-Origin in South Pars gas field from Persian Gulf, Iran. Journal of Petroleum Science and Engineering, 86/87, 217-224.

[16] Li, M. J., Wang, T. G., Lillis, P. G., Wang, C. J., & Shi, S. B. (2012). The significance of 24-norcholestanes, triaromatic steroids and dinosteroids in oils and Cambrian–Ordovician source rocks from the cratonic region of the Tarim Basin. NW China Applied Geochemistry, 7(8), 1643-1654.

[17] Hakimi, M. H., Abdullah, W. H., & Shalaby, M. R. (2012). Madbi-Biyadh/Qishn (!) petroleum system in the onshore Masila Basin of the Eastern Yemen. Marine and Petroleum Geology, 35(1), 116-127.

[18] Ghadeer, S. G., & Macquaker, J. H. S. (2012). The role of event beds in the preservation of organic carbon in fine-grained sediments: Analyses of the sedimentological processes operating during deposition of the Whitby Mudstone Formation (Toarcian, Lower Jurassic) preserved in northeast England Marine and Petroleum Geology. Mar. Petrol. Geol., 5(1), 309-320.

[19] Sachse, V. F., Littke, R., Jabour, H., Schümann, T., & Kluth, O. (2012). Late Cretaceous (Late Turonian, Coniacian and Santonian) petroleum source rocks as part of an OAE, Tarfaya Basin, Morocco. Marine and Petroleum Geology, 29(1), 35-49.

[20] Fu, J. M., & Liu, D. H. (1992). Natural gas migration, accumulation and sealing conditions. Beijing: Science Press.

[21] Zhang, H. F. (1999). Petroleum geology. Beijing: Petroleum Industry Press.

[22] Li, M. C. (2004). Oil and gas migration (3rd ed.). Beijing: Petroleum Industry Press.



  • There are currently no refbacks.

Copyright (c)

Share us to:   


  • How to do online submission to another Journal?
  • If you have already registered in Journal A, then how can you submit another article to Journal B? It takes two steps to make it happen:

1. Register yourself in Journal B as an Author

  • Find the journal you want to submit to in CATEGORIES, click on “VIEW JOURNAL”, “Online Submissions”, “GO TO LOGIN” and “Edit My Profile”. Check “Author” on the “Edit Profile” page, then “Save”.

2. Submission

  • Go to “User Home”, and click on “Author” under the name of Journal B. You may start a New Submission by clicking on “CLICK HERE”.

We only use three mailboxes as follows to deal with issues about paper acceptance, payment and submission of electronic versions of our journals to databases:;;

 Articles published in Advances in Petroleum Exploration and Development are licensed under Creative Commons Attribution 4.0 (CC-BY)


Address:1055 Rue Lucien-L'Allier, Unit #772, Montreal, QC H3G 3C4, Canada.

Telephone: 1-514-558 6138
Website: Http://

Copyright © 2010 Canadian Research & Development Centre of Sciences and Cultures