【摘要】 对于包含两组垂直裂缝的各向同性地层,正交各向异性介质是与实际地层最符合的地质模型.本文根据等效理论将裂缝介质等效为各向异性介质.研究发现裂缝介质P波速度与时距曲线具有强烈的方位各向异性特征,且各向异性参数随方位周期性变化.根据最小二乘的方法反演各向异性参数,首先选取三条呈一定角度的测线根据P波速度反演裂缝方位角,然后根据本文的方法反演各向异性参数以及裂缝参数.分别用信噪比为10,5,1的地震数据,该方法能得到准确的裂缝参数,证明了该方法的稳定性和抗噪性.模型试算表明,本文提出的方法可以得到较高精度的裂缝方位角以及裂缝参数,为利用地震数据进行精确的裂缝参数反演提供依据.更多还原

【Abstract】 Orthorhombic model is the simplest model used to describe realistic fractured reservoirs in orthogonal fracture systems in purely isotropic layer. Fracture medium is equivalented to the anisotropic medium using the equivalent theory.The P-wave velocity and P-wave traveltime-distance curves show strong azimuthal anisotropy and anisotropy parameters Periodic change along with the azimuth.Based on the least squares method to the inverse the anisotropic parameters and P-wave velocity and fracture parameters.We can get the accurate fracture parameters when using the seismic data with noise which provides the stability and noise resistance of the method.The model result show that the proposed method can get higher accuracy of fracture azimuth and fracture parameters,which provide a basis for accurate inversion using the seismic data.更多还原