Inversion method of fracture density based on spatial constraints
Due to the large error in conventional indirect prediction of fracture density using normal weakness and tangential weakness,this paper proposes a direct inversion method for fracture density in carbonate rocks(HTI medium).Based on the inversion of amplitudes varying with offset and azimuth(AVAZ),the paper in-troduces an inverse distance weighted method to optimize the transverse difference operator of traditional aniso-tropic total variational(ATV)multichannel inversion.The method fully utilizes the correlation between adja-cent seismic tracks to further improve the horizontal continuity and stability of the inversion algorithm.Lateral constraints,low-frequency constraints,and sparse constraints are applied to construct the inversion objective function,and the alternate direction multiplier method(ADMM)is adopted to optimize the inversion objective function.With the two advantages of direct inversion of fracture density and inverse distance weighted interpola-tion,model tests are conducted on the Marmousi Ⅱ model to verify the effectiveness and noise resistance of the proposed method.Then,the paper further verifies the practical feasibility of the proposed method by applying it to the actual data of carbonate rocks in YM block,Tarim Basin.The proposed method is more accurate and reli-able for predicting fracture density and can be widely applied in similar areas.
万方数据
维普
