The Application of Improved Wavelet Deconvolution Algorithm in Gas Hydrate Seismic Data Processing

Abstract

Abstract:

The seismic prospecting of gas hydrate requires fine description to the gas hydrate orebody in threedimensional space. The highresolution seismic data should be obtained, and deconvolution of seismic data processing is the primary means to improve resolution. On the basis of traditional wavelet deconvolution algorithm, we designed an improved wavelet deconvolution algorithm. By filtering of logarithmic power spectrum of seismic records, this algorithm could not only recognize BSR(Bottom Simulating Reflector) effectively, but also overcome the influence of nonwhite noise. The spectral crosscorrelation average instead of arithmetic mean, can effectively improve the seismic data resolution. It is simple and convenient to extract wavelet by Hilbert transform algorithm. Seismic data of northern South China Sea line HS621 processing with improved wavelet deconvolution algorithm shows that the algorithm can not only track BSR stably and clearly, but also can effectively improve the seismic data resolution to meet the natural gas hydrate seismic data fine processing.

Key words: gas hydrate, BSR, wavelet deconvolution, Hilbert transformation, northern South China Sea

CLC Number:

P631.4

ZHANG Xin, Pang Wen-Yong, LEI Xin-Hua, SHA Zhi-Bin. The Application of Improved Wavelet Deconvolution Algorithm in Gas Hydrate Seismic Data Processing[J]. Geoscience, 2010, 24(3): 501-505.

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