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在方位各向异性介质中，方位各向异性的主方向就是准纵波和准横波传播的方向，即准纵波和准横波为纯纵波和纯横波方式的方向。如果方位各向异性是由作用于一个方位各向同性背景中的定向垂直裂缝引起的，则这些主方向中的其中两个对应平行和垂直于裂缝的方向。横波穿过一个方位各向异性介质时，对与主方向有关的传播方向很敏感。因此，可以用一次横波或多分量转换横波资料来获得主方向。除了采集费用高外，多分量资料处理和解释还需要一种地震工业目前还没有完全开发的技术。另外，利用常规纵波资料检验各向异性也只限于一些不同方向的ＡＶＯ定性研究。定量研究方位ＡＶＯ，就是研究纵波资料在固定偏移距处振幅随方位的变化。研究结果显示振幅随方位角的变化是以２φ为周期的，其中φ是相对于一个主方向的激发方向的取向。对于裂缝感应各向异性，主方向对应平行或垂直于裂缝的方向。用纵波反射振幅的这个呈周期的方位关系来识别两种显著的各向异性检测情况。第一种情况是一个完全确定情况，针对这种情况我们已经用三种方位测线对每个共中心点（ＣＭＰ）位置进行了观测，并推导出这种情况下计算主方向的取向方程。第二种情况是一个超定情况，针对这种情况用三个方位以上的测线进行了观测。这种超定情况中?
In the azimuthally anisotropic medium, the main azimuthal anisotropy is the direction of quasi-longitudinal and quasi-transverse waves, that is, the quasi-longitudinal and quasi-transverse waves are the directions of the pure longitudinal wave and the pure transverse wave. If azimuthal anisotropy is caused by directional vertical cracks acting in an azimuthally isotropic background, two of these main directions correspond to directions parallel and perpendicular to the fracture. When a transverse wave passes through an azimuthally anisotropic medium, it is very sensitive to the propagation direction associated with the main direction. Therefore, the primary direction can be obtained by using one-time transverse or multi-component converted shear wave data. In addition to the high cost of acquisition, multi-component data processing and interpretation also require a technology currently not yet fully developed by the seismic industry. In addition, the use of conventional longitudinal wave data to test the anisotropy is only limited to a number of different directions of AVO qualitative research. Quantitative research azimuth AVO, is to study the longitudinal wave data at a fixed offset amplitude with the azimuth change. The results show that the variation of amplitude with azimuth is periodic with 2φ, where φ is the orientation of the excitation direction with respect to one main direction. For crack induction anisotropy, the main direction corresponds to the direction parallel or perpendicular to the crack. This periodical azimuthal relationship of the amplitude of the longitudinal wave reflection is used to identify two significant anisotropy detections. The first case is a fully definitive case, in which case we have observed each co-centered (CMP) position with three azimuth lines and derived the orientation equation for calculating the main direction in this case. The second case is an over-determined situation, for which observations were made with more than three azimuths. This overdetermined situation?