A band-limited and robust inverse Q filtering algorithm
Chen Zengbao1,2, Chen Xiaohong1,2, Li Jingye1,2, Wang Benfeng1,2, Ma Sha3
1. State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Beijing 102249, China;
2. National Engineering Laboratory for Offshore Oil Exploration, China University of Petroleum (Beijing), Beijing 102249, China;
3. Sinochem Petroleum Exploration & Production Co. Ltd., Beijing 100031, China
Abstract：Inverse Q filtering in Gabor domain makes use of Gabor spectrum instead of the downward wavefield. It performs stabilized inverse Q filtering in 2-D time-frequency spectrum, and reconstructs seismic traces in the time-domain. Compared with the layered implementation of inverse Q filtering, this algorithm may use a more accurate earth Q model without 2D amplitude compensation operator approximation. So its efficiency and accuracy are much higher. In order to improve the compensation effect without boosting the ambient noise, we perform inverse Q filtering in Gabor domain by incorporating a time-variant passband filter. The high-cut frequency of this passband filter follows a hyperbolic trajectory of a seismic signal travel time at a specified point as the signal bandwidth varies in media due to the attenuation. Test results on theoretical and real data demonstrate that the inverse Q filtering algorithm incorporating a time-variant passband filter is robust and effective for seismic noisy data, and improves seismic resolution with no S/N degradation.
