Abstract
Rock physics modeling is implemented for shales in the Luojia area of the Zhanhua topographic depression. In the rock physics model, the clay lamination parameter is introduced into the Backus averaging theory for the description of anisotropy related to the preferred alignment of clay particles, and the Chapman multi-scale fracture theory is used to calculate anisotropy relating to the fracture system. In accordance with geological features of shales in the study area, horizontal fractures are regarded as the dominant factor in the prediction of fracture density and anisotropy parameters for the inversion scheme. Results indicate that the horizontal fracture density obtained has good agreement with horizontal permeability measured from cores, and thus confirms the applicability of the proposed rock physics model and inversion method. Fracture density can thus be regarded as an indicator of reservoir permeability. In addition, the anisotropy parameter of the P-wave is higher than that of the S-wave due to the presence of horizontal fractures. Fracture density has an obvious positive correlation with P-wave anisotropy, and the clay content shows a positive correlation with S-wave anisotropy, which fully shows that fracture density has a negative correlation with clay and quartz contents and a positive relation with carbonate contents.
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This research is sponsored by the National Natural Science Foundation of China under Grants 41404090, U1262208, and U1663207, and the Foundation of the SinoPEC Key Laboratory of Shale Oil/Gas Exploration and Production Technology under Grants No. G5800-15-ZS-WX039, and the project under Grants No. G5800-15-ZS-WX004.
Guo Zhi-Qi: See biography and photo in the Applied Geophysics June 2015 issue, P. 198.
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Guo, ZQ., Liu, C., Liu, XW. et al. Research on anisotropy of shale oil reservoir based on rock physics model. Appl. Geophys. 13, 382–392 (2016). https://doi.org/10.1007/s11770-016-0554-0
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DOI: https://doi.org/10.1007/s11770-016-0554-0