叠前同时反演技术在碳酸盐岩储层预测中的应用

四川盆地川中龙岗地区雷口坡组雷四³ 亚段为低孔、低渗白云岩储层，与石灰岩（非储层）的波阻抗差异小，利用叠后反演技术难以有效预测储层。从测井岩石物理分析入手，利用参数 λρ，μρ和 v_P/v_S 构建了对储层更敏感的储层指示因子，然后使用叠前同时反演技术计算出该指示因子，并进行了储层预测。经钻井证实，利用储层指示因子进行储层预测的结果吻合程度高，说明叠前同时反演技术是复杂碳酸盐岩储层预测的一种有效手段。

Application of prestack simultaneous inversion to the prediction of carbonate reservoirs

The reservoir at the top of Leikoupo Formation in Central Sichuan Basin has the characters of low porosity and low permeability. Well log data shows that the P-impendence of gas-bearing dolomites is similar with tense limestone. Therefore, traditional method is incapable to discriminate porous dolomite and tense limestone. For resolving this problem, first, this paper conducted sensitivity analysis by using log crossplot technique to find out rock physical parameters which are sensitive to reservoir and fluids, and then calculated the sensitive parameters such as λρ,μρ and Vp/Vs by prestack simultaneous inversion and predicted the favorable reservoirs. The results fit well with the drilling data, which shows that this method is feasible in complex carbonate reservoir prediction.