Estimation of quality factors by energy ratio method
Wang Zong-Jun1,2, Cao Si-Yuan2, Zhang Hao-Ran3, Qu Ying-Ming4, Yuan Dian2, Yang Jin-Hao2, and Shao Guan-Ming2
1. CNOOC Research Institute, Beijing 100028, China.
2. State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Beijing 102249, China.
3. Shenzhen Branch of CNOOC Ltd., Guangzhou 510240, China.
4. School of Geosciences, China University of Petroleum, Qingdao 266580, China.
Abstract：
The quality factor Q, which reflects the energy attenuation of seismic waves in subsurface media, is a diagnostic tool for hydrocarbon detection and reservoir characterization. In this paper, we propose a new Q extraction method based on the energy ratio before and after the wavelet attenuation, named the energy-ratio method (ERM). The proposed method uses multipoint signal data in the time domain to estimate the wavelet energy without invoking the source wavelet spectrum, which is necessary in conventional Q extraction methods, and is applicable to any source wavelet spectrum; however, it requires high-precision seismic data. Forward zero-offset VSP modeling suggests that the ERM can be used for reliable Q inversion after nonintrinsic attenuation (geometric dispersion, reflection, and transmission loss) compensation. The application to real zero-offset VSP data shows that the Q values extracted by the ERM and spectral ratio methods are identical, which proves the reliability of the new method.
Wang Zong-Jun,Cao Si-Yuan,Zhang Hao-Ran et al. Estimation of quality factors by energy ratio method[J]. APPLIED GEOPHYSICS, 2015, 12(1): 86-92.
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2015, Vol. 12 
