Rock physics modeling method of natural gas hydrate based on equivalent medium theory
YANG Wenqiang1, ZONG Zhaoyun1,2, JIANG Man1, LIU Xinxin2,3
1. School of Geosciences, China University of Petroleum(East China), Qingdao, Shandong 266580, China; 2. Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266580, China; 3. Qingdao Institute of Marine Geology, China Geology Survey, Qingdao, Shandong 266071, China
Abstract：Seismic rock-physics modelling is a bridge used to quantitively convert observed seismic information into the physical properties of reservoir. A reasonable rock-physics model is an important theo-retical basis for seismic response analysis, saturation prediction and pre-stack seismic inversion of gas hydrate reservoir. However, gas hydrate can be either a part of rock matrix or a pore-filler, and this complicated composition may cause uncertainty and errors. Based on the equivalent medium theory, this paper presents a rock-physics model, which considers the shear modulus of hydrates and hydrates stored in pores and matrix at the same time. Particularly, the ratio between hydrates stored in pores and matrix is dynamic and can be updated by an iterative process constrained by P-wave velocity form well logging data. This model can be used to support for the prediction of S-wave velocity and saturation in gas hydrate layers, and has been validated by real logging data from well SH2 in a sea area.
杨文强, 宗兆云, 姜曼, 刘欣欣. 基于等效介质理论的天然气水合物岩石物理建模方法[J]. 石油地球物理勘探, 2021, 56(3): 528-535.
YANG Wenqiang, ZONG Zhaoyun, JIANG Man, LIU Xinxin. Rock physics modeling method of natural gas hydrate based on equivalent medium theory. Oil Geophysical Prospecting, 2021, 56(3): 528-535.
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