Abstract
Rock-physics models are constructed for hydrate-bearing sediments in the Qilian Mountains permafrost region using the K–T equation model, and modes I and II of the effective medium model. The K–T equation models the seismic wave propagation in a twophase medium to determine the elastic moduli of the composite medium. In the effective medium model, mode I, the hydrate is a component of the pore inclusions in mode I and in mode II it is a component of the matrix. First, the P-wave velocity, S-wave velocity, density, bulk modulus, and shear modulus of the sediment matrix are extracted from logging data.. Second, based on the physical properties of the main components of the sediments, rockphysics model is established using the K–T equation, and two additional rock-physics models are established assuming different hydrate-filling modes for the effective medium. The model and actual velocity data for the hydrate-bearing sediments are compared and it is found that the rock-physics model for the hydrate-filling mode II well reproduces the actual data.
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We are grateful for the support of the Institute of Geophysical and Geochemical Exploration (IGGE) CAGS. We also thank the reviewers and editors for their comments and valuable suggestions, and appreciate their help. Best wishes for everyone.
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This work was supported by the Institute of Geophysical and Geochemical Exploration (IGGE) CAGS of China (No. WH201207).
Liu Jie, is a post-doctor who received his Ph.D. degree of geodetection and information technology from China University of Geosciences (Wuhan) in 2015. His main interests are rock physics and seismic wave propagation in hydrate-bearing sediments.
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Liu, J., Liu, JP., Cheng, F. et al. Rock-physics models of hydrate-bearing sediments in permafrost, Qilian Mountains, China. Appl. Geophys. 14, 31–39 (2017). https://doi.org/10.1007/s11770-017-0608-y
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DOI: https://doi.org/10.1007/s11770-017-0608-y