Abstract:The attenuation is an important indicator of reservoir lithology.It is usually measured by quality factor Q.The Q value extraction is of great significance for gas-bearing reservoir prediction.In this paper,we propose a new Q value estimation with introduced Capon2D,which means an improvement with a weighting.The accuracy and stability of the proposed method are tested by statistical experiments.Based on model experiments,the proposed method has better robustness to high-frequency noise,and stronger ability to suppress the wavelet interference than conventional spectral ratio methods.For real data tests,a relatively stable and accurate Q value estimation is obtained from 3D seismic poststack data.Finally,the proposed method is applied to the reservoir Q value estimation in the shale exploration in Sichuan Basin.The estimated high-Q zone matches very well with the reservoir fracture-zone,which proves that this estimation may be used as an indicator for gas bearing in shale reservoirs.
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