Discriminating gas and water using multi-angle extended elastic impedance inversion in carbonate reservoirs
碳酸盐岩储层多角度弹性阻抗流体识别方法

AVO response for carbonate reservoirs is fainter than the crack reservoirs.So it is very hard to discriminate gas and water in carbonate reservoirs using elastic impedance(EI),even under the optimal incident angle.In this paper,we propose a novel method for discriminating gas and water using multi-angle extended elastic impedance(MEEI)inversion in carbonate reservoirs.We establish the fluid-bearing patterns and effective criterion for discriminating gas and water by computing MEEI of target layers using the known well data.MEEI inversion of real seismic data shows that we can judge whether the reservoir is good or bad and is gas-bearing or water-bearing by observing EEI trend varying with various incident angles.The efficiency of the proposed methods is validated by the application of real data in Sichuan basin.