利用P波层间时差确定裂缝性地层的各向异性参数

Determining the anisotropic parameters of fractured formation by using P-wave interval moveout

地下定向裂缝是低渗透率油气藏油气储集、运移的通道，对油气的开采有着重要的意义。本文研究了层间时差沿方位的变化规律，给出了层间时差与裂缝性地层各向异性参数的关系；以此为基础，在彼此相交呈45°角的4条二维P波测线的CDP道集上，拾取层间时差，求得各向异性参数，并由此对地下裂缝的发育及分布作出判断。模型研究表明，利用本方法能够较精确地获得地下裂缝性地层的各向异性参数。文中还讨论了将层间时差方法应用于实际常规二维、三维P波资料的可能情况。

Directional fractures in formations are the passages through which hydrocarbon accumulates and migrates in low permeable reservoir, and they are very significant to hydrocarbon recovery.Authors describe how P-wave interval moveout varies with azimuth, and offer the relation between the interval moveout and anisotropic parameter in fractured formation. Interval moveouts of CDP trace gathers of 4 seismic P-wave lines which intersect in 45°one by one are picked to estimate anisotropic parameters, which are used to ascertain fractures in an interested formation. Modeling research shows that the method may be used to know the anisotropic parameters of fractured formation.Authors also discuss the possibility of applying this method to real 2-D and 3-D P-wave data.