Anisotropy rock physics model for the Longmaxi shale gas reservoir, Sichuan Basin, China
Liu Xi-Wu1,2,3, Guo Zhi-Qi4, Liu Cai4, and Liu Yu-Wei1,2,3
1. State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, Beijing 100083, China.
2. SinoPEC Key Laboratory of Shale Oil/Gas Exploration and Production Technology, Beijing 100083, China.
3. SinoPEC Petroleum Exploration and Production Research Institute, Beijing 100083, China.
4. Jilin University, Changchun 130021, China.
Abstract：
The preferred orientation of clay minerals dominates the intrinsic anisotropy of shale. We introduce the clay lamination (CL) parameter to the Backus averaging method to describe the intrinsic shale anisotropy induced by the alignment of clay minerals. Then, we perform the inversion of CL and the Thomsen anisotropy parameters. The direct measurement of anisotropy is difficult because of the inability to measure the acoustic velocity in the vertical direction in boreholes and instrument limitations. By introducing the parameter CL, the inversion method provides reasonable estimates of the elastic anisotropy in the Longmaxi shale. The clay content is weakly correlated with the CL parameter. Moreover, the parameter CL is abnormally high at the bottom of the Longmaxi and Wufeng Formations, which are the target reservoirs. Finally, we construct rock physics templates to interpret well logging and reservoir properties.
Hou Zhen-Long,Wei Xiao-Hui,Huang Da-Nian et al. Anisotropy rock physics model for the Longmaxi shale gas reservoir, Sichuan Basin, China[J]. APPLIED GEOPHYSICS, 2017, 14(1): 21-30.
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2017, Vol. 14 
