中文摘要：

AVAZ方法是裂缝储层评价的重要手段,然而它受到静态等效地震岩石物理模型的限制,一般用于反演裂缝密度和裂缝走向。近年来,随着裂缝性孔隙介质等效模型的发展,频变AVAZ响应特征被证明可以携带更多的裂缝性质信息。本文针对HTI介质,基于Chapman理论分析流体类型和裂缝长度对频变AVAZ响应特征的影响并建立结合贝叶斯理论和遗传算法反演裂缝密度、裂缝走向、裂缝长度和裂缝充填流体类型的新方法。新反演方法流程为：首先,基于频变AVAZ特征建立反演目标函数并运用遗传算法求解,根据此结果分别建立裂缝参数的似然函数;其次,利用贝叶斯算法将地质、测井等获得的裂缝性质先验信息与地震获得的裂缝性质似然函数结合,计算裂缝性质的后验概率分布函数;最后,通过控制先验裂缝参数的方差,均衡地震数据及地质、测井数据的信息采用量。合成数据的分析和反演结果表明：流体性质和裂缝长度是频变AVAZ响应的敏感参数;本文提出反演裂缝性质方法是可行的。先验裂缝参数影响分析验证了该方法在均衡地质、测井及地震数据的信息采用量方面的有效性。

英文摘要：

AVAZ method plays an important role in characterizing fracture reservoirs. However,only fracture density and azimuth can be estimated with the limitation of traditional equivalent medium theories. In recent years, with the development of equivalentmedium theories considering attenuation and dispersion have shown that containing more fracture properties. Based on Chapman theory,this paper analysis frequency-dependent AVAZ attributes effected by fluid type and fracture length,and establish a new inversion method which combine Bayes theory and genetic algorithm. The flow of inversion method： Firstly,construct objective function based on frequency-dependent AVAZ attributes and obtain the solution by genetic algorithm. According the solution establish likelihood function of fracture properties, respectively. Then calculate the posterior probability distribution function of fracture properties by combining prior information from geology, well logging and likelihood function from seismic inversion. Finally, balance the adoptions of seismic information and geology, well logging information through controlling variance of prior fracture parameters.Analysis and inversion on synthetic data shows that fluid type and fracture length are sensitive to frequency-dependent AVAZ response and the inversion method of fracture properties in this paper is feasible. Analysis of the influence of prior information verifies that this method is efficient on balancing the adoption of geology,well and seismic data.