Reservoir information extraction using a fractional Fourier transform and a smooth pseudo Wigner-Ville distribution
Wang Zhu-Wen1, Wang Xiao-Li1,2, Xiang Min1, Liu Jing-Hua1, Zhang Xue-Ang1, and Yang Chuang1
1. College of Geo-exploration Science and Technology, Jilin University, Changchun 130026, China.
2. Editorial Department of Journal of Jilin University, Changchun 130026, China.
Abstract：
Currently, it is diffi cult for people to express signal information simultaneously in the time and frequency domains when analyzing acoustic logging signals using a simple-time or frequency-domain method. It is diffi cult to use a single type of time-frequency analysis method, which affects the feasibility of acoustic logging signal analysis. In order to solve these problems, in this paper, a fractional Fourier transform and smooth pseudo Wigner- Ville distribution (SPWD) were combined and used to analyze array acoustic logging signals. The time-frequency distribution of signals with the variation of orders of fractional Fourier transform was obtained, and the characteristics of the time-frequency distribution of different reservoirs under different orders were summarized. Because of the rotational characteristics of the fractional Fourier transform, the rotation speed of the cross terms was faster than those of primary waves, shear waves, Stoneley waves, and pseudo Rayleigh waves. By choosing different orders for different reservoirs according to the actual circumstances, the cross terms were separated from the four kinds of waves. In this manner, we could extract reservoir information by studying the characteristics of partial waves. Actual logging data showed that the method outlined in this paper greatly weakened cross-term interference and enhanced the ability to identify partial wave signals.
WANG Zhu-Wen,WANG Xiao-Li,XIANG Min et al. Reservoir information extraction using a fractional Fourier transform and a smooth pseudo Wigner-Ville distribution[J]. APPLIED GEOPHYSICS, 2012, 9(4): 391-400.
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2012, Vol. 9 
