SEISMIC ANISOTROPIC MODELING OF FRACTURE-FILLING GAS HYDRATE

QIAN Jin; WANG Xiujuan; DONG Dongdong; WU Shiguo

doi:10.16562/j.cnki.0256-1492.2015.04.016

2015 Vol. 35, No. 4

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Article navigation > Marine Geology & Quaternary Geology > 2015 > 35(4): 149-154

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QIAN Jin, WANG Xiujuan, DONG Dongdong, WU Shiguo. SEISMIC ANISOTROPIC MODELING OF FRACTURE-FILLING GAS HYDRATE[J]. Marine Geology & Quaternary Geology, 2015, 35(4): 149-154. doi: 10.16562/j.cnki.0256-1492.2015.04.016

Citation:

QIAN Jin, WANG Xiujuan, DONG Dongdong, WU Shiguo. SEISMIC ANISOTROPIC MODELING OF FRACTURE-FILLING GAS HYDRATE[J]. Marine Geology & Quaternary Geology, 2015, 35(4): 149-154. doi: 10.16562/j.cnki.0256-1492.2015.04.016

SEISMIC ANISOTROPIC MODELING OF FRACTURE-FILLING GAS HYDRATE

1. Key Laboratory of Marine Geology and Environment, Chinese Academy of Sciences, Qingdao 266071, China;
2. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China

Received Date: 12 October 2014

Revised Date: 15 November 2014

Abstract

Abstract

Gas hydrate, existed as solid nodules or near-vertical veins filled in high angle fractures, is widely developed in the argillaceous deposits in deep basins. Such a fracture-filling gas hydrate may produce an anisotropic anomaly of high apparent resistivity. However, seismic wave propagation in the anisotropic hydrate layer is unclear. In this paper, a geophysical model of hydrate layer as such is established on the basis of logging data including velocity, density and dip of NGHP01-10 in the Krishna-Godavari (KG) basin of India. Then seismic response and propagation of gas hydrate-filled in fractures are modeled both in isotropic and anisotropic elastic wave conditions using the staggered-grid finite-difference method. Seismic modeling results show that isotropic velocity and amplitude are significantly different from anisotropic velocity and amplitude for gas hydrate-filled in fractures. Not only there are more reflections in anisotropic hydrate than those in isotropic hydrate, but also the average velocities of anisotropy are faster than those of isotropy.
- gas hydrate /
- fracture /
- anisotropy /
- modeling

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References

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