RESEARCH PAPER

Prestack inversion identification of organic reef gas reservoirs of Permian Changxing Formation in Damaoping area, Sichuan Basin, SW China

  • Lu ZHOU ,
  • Feiyan ZHONG ,
  • Jiachen YAN ,
  • Kexiu ZHONG ,
  • Yong WU ,
  • Xihui XU ,
  • Peng LU ,
  • Wenji ZHANG ,
  • Yi LIU
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  • 1. State Key Laboratory of Oil and Gas Reservoir and Exploration, Southwest Petroleum University, Chengdu 610500, China
    2. School of Geosciences and Technology, Southwest Petroleum University, Chengdu 610500, China
    3. School of Electrical Engineering and Information, Southwest Petroleum University, Chengdu 610500, China
    4. China Oilfield Service Limited Geophysical Division, Tianjin 300451, China
    5. Chongqing Division, PetroChina Southwest Oil & Gas Field Company, Chongqing 400021, China
    6. Sichuan Province Key Laboratory of Natural Gas Geology, Chengdu 610500, China
    7. Southwest Branch, CNPC Logging Company Limited, Chongqing 400021, China

Received date: 2019-01-09

  Revised date: 2020-01-02

  Online published: 2020-02-19

Supported by

Supported by the National Natural Science Foundation of China(41430316);China National Science and Technology Major Project(2017ZX05008-004-008)

Abstract

Organic reef reservoirs in the platform margin of Kaijiang-Liangping trough in Damaoping area, Sichuan Basin are thin in single layer, fast in lateral variation, and have small P-impedance difference from the surrounding rock, it is difficult to identify and predict the reservoirs and fluid properties by conventional post-stack inversion. Through correlation analysis of core test data and logging P-S wave velocity, this work proposed a formula to calculate the shear wave velocity in different porosity ranges, and solved the issue that some wells in the study area have no S-wave data. AVO forward analysis reveals that formation porosity is the main factor affecting the variation of AVO type, the change of water saturation cannot affect the AVO type, but it has an effect on the change range of AVO. Through cross-plotting analysis of elastic parameters, it is found that fluid factor is a parameter sensitive to gas-bearing property of organic reef reservoir in the study area. By comparing results of post-stack impedance inversion, post-stack high frequency attenuation property, pre-stack simultaneous inversion and AVO anomaly analysis of angle gathers, it is found that the gas-bearing prediction of organic reef reservoirs by using fluid factor derived from simultaneous pre-stack inversion had the highest coincidence rate with actual drilling data. At last, according to the characteristics of fluid factor distribution, the favorable gas-bearing area of the organic reef reservoir in Changxing Formation was predicted, and the organic reef trap at the top of Changxing Formation in Block A of Damaoping area was sorted out as the next exploration target.

Cite this article

Lu ZHOU , Feiyan ZHONG , Jiachen YAN , Kexiu ZHONG , Yong WU , Xihui XU , Peng LU , Wenji ZHANG , Yi LIU . Prestack inversion identification of organic reef gas reservoirs of Permian Changxing Formation in Damaoping area, Sichuan Basin, SW China[J]. Petroleum Exploration and Development, 2020 , 47(1) : 89 -100 . DOI: 10.1016/S1876-3804(20)60008-8

References

[1] YIN Xingyao, CAO Danping, WANG Baoli , et al. Advances in fluid identification based on prestack seismic inversion. Oil Geophysical Prospecting, 2014,49(1):22-34.
[2] SHUEY R T . A simplification of the zoeppritz equations. Geophysics, 1985,50(4):609-614.
[3] CONNOLLY P . Elastic impedance. The Leading Edge, 1999,18(4):438-452.
[4] HAMPSON D P, RUSSELL B H, BANKHEAD B . Simultaneous inversion of pre-stack seismic data. Houston: SEG Annual Meeting, 2005: 1635-1638.
[5] FATTI J L, SMITH G C, VAIL P J , et al. Using AVO analusis: A 3D case history using geosack technique. Geophysics, 1994,59:1362-1376.
[6] HAN Jiaxing . Pre-stack simultaneous inversion and application in reservoir prediction in Chunguang oilfield. Chengdu: Chengdu University of Technology, 2016.
[7] LANG Xiaoling, PENG Shibi, KANG Hongquan , et al. Application of prestack simultaneous inversion in fluid identification. Geophysical Prospecting for Petroleum, 2010,49(2):164-169.
[8] LI Xueyi . A discussion on the technical difficulties and countermeasures to carry out seismic exploration in the carbonate rock areas of Sichuan Basin. Natural Gas Industry, 2000,20(2):12-17.
[9] ZHOU Lu, REN Benbing, WU Yong , et al. The seismic response feature and the distribution prediction of oolitic beachs of Feixianguan Formation in the northern Sichuan Basin. Chinese Journal of Geology, 2016,51(2):425-447.
[10] ZHOU Lu, YUAN Bing, SONG Yong , et al. A seismic quantitative identification method of slope break belt. Petroleum Exploration and Development, 2016,43(6):940-948.
[11] NENG Yuan, YANG Haijun, DENG Xingliang . Structural patterns of fault broken zones in carbonate rocks and their influences on petroleum accumulation in Tazhong Paleo-uplift, Tarim Basin, NW China. Petroleum Exploration and Development, 2018,45(1):40-50, 127.
[12] WU Hengzhi, WU Yajun, KE Guangming , et al. Bioherm development model and reservoir prediction of Changxing Formation in Yuanba Area, Northeastern Sichuan Basin. Oil and Gas Geology, 2017,38(4):645-657.
[13] ZOU Caineng, XU Chunchun, WANG Zecheng , et al. Geological characteristics and forming conditions of the large platform margin reef-shoal gas province in the Sichuan Basin. Petroleum Exploration and Development, 2011,38(6):641-651.
[14] LI Yang, KANG Zhijiang, XUE Zhaojie , et al. Theories and practices of carbonate reservoirs development in China. Petroleum Exploration and Development, 2018,45(4):669-678.
[15] LIU Zhicheng, ZHANG Tingshan, DANG Lurui , et al. Reef- forming types and distribution of organic reefs in Changxing Formation of northeastern Sichuan area. Geology in China, 2011,38(5):1298-1311.
[16] NIE Wancai, ZHENG Chao, DU Jiangmin , et al. Characteristics research of the reef reservoir in Changxing Formation, Damaoping structure of East Sichuan. Journal of Chongqing University of Science and Technology(Natural Sciences Edition), 2011,13(3):40-42.
[17] ZHOU Lu, LI Dong, WU Yong , et al. The seismic response characteristics and distribution of the reefs in the Changxing Formation, northern Sichuan Basin. Acta Petrologica Sinica, 2017,33(4):1189-1203.
[18] REN Xingguo, LUO Li, YAO Shengxian , et al. Logging prediction of organic reef in east of Sichuan. Petroleum Exploration and Development, 2000,27(1):41-43.
[19] XU Cuixia, MA Pengshan, LAI Lingbin , et al. Sensitivity parameters of tight sand gas: A case study of Lower Cretaceous Yingcheng Formation of Yingtai gas field in Songliao Basin, NE China. Petroleum Exploration and Development, 2014,41(6):712-716.
[20] LI Luxi. YIN Xingyao, CAO Danping , et al. Methodology and application of oil/water identification based on fluid factor pre-stack seismic inversion. Computerized Tomography Theory and Applications, 2016,25(1):33-40.
[21] XU Xiaoyong, LI Rui, XU Minghua , et al. S-wave velocity estimation of biological shoal reservoir on right bank of Amudarya. Journal of Chengdu University of Technology(Science and Technology Edition), 2015,42(2):225-230.
[22] WANG Xian, LI Wenjie, HE Luming , et al. Shear wave estimation quality control method. Journal of Oil and Gas Technology, 2011,33(9):87-91.
[23] ZHOU Shuisheng, YI Wei, HAO Zhaobing , et al. Experiment research and application of fluid sensitive attributes based on the pre-stack inversion. Chinese Journal of Geophysics, 2012,55(6):1985-1992.
[24] GU Mingfeng, XU Meiru, ZHOU Jingao , et al. Application of prestack simultaneous inversion to the prediction of carbonate reservoirs. Lithologic Reservoirs, 2013,25(2):60-64.
[25] GOODWAY B, CHEN T W, DOWNTON J . Improved AVO fluid detection and lithology discrimination using Lamé petrophysical parameters: “λρ”, “μρ”, & “λ/μ fluid stack”, from P and S inversion. Houston: SEG Technical Program Expanded Abstracts, 1997: 183-186.
[26] YIN Xingyao, ZHANG Fanchang, SUN Chengyu , et al. Prestack seismic inversion. Beijing: China University of Petroleum Press, 2010.
[27] RUTHERFORD S R, WILLIAMS R H . Amplitude-versus- offset variations in gas sands. Geophysics, 1989,54(6):680-688.
[28] CASTAGNA J P, SWAN H W . Principles of AVO crossplotting. The Leading Edge, 1997,16(4):337-342.
[29] ZHANG Shaohong . Analysis of rock-physical properties through angle-gather sections. Journal of Xi’an Shiyou University(Natural Science Edition), 2007,22(5):18-20.
[30] WEI Liuyang, JIA Ganggang, XIAO Wei , et al. Forward modeling of wave equation of bioherm model and analysis of seismic response characteristics. Journal of Yangtze University(Natural Science Edition), 2013,10(26):75-78.
[31] JIANG Yan, XU Liheng, ZHANG Xiuli , et al. Prestack geostatistical inversion method and its application on the reservoir prediction of Changyuan oilfield. Progress in Geophysics, 2013,28(5):2579-2586.
[32] TANG Jie, GUO Yuan, SUN Chengyu , et al. Experiment study of wave velocity and elastic modules variation characteristics for carbonates. Journal of China University of Petroleum(Edition of Natural Science), 2012,36(5):62-66.
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