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地壳岩石的各向异性可能是由于裂隙、应力不等、颗粒有一定排列方向或微细层理所引起。有微细层理的岩石可用横向各向同性固体来代表,其对称轴垂直于地层。在这种介质内点力发出的波用位移的二重傅里叶变换的数值求逆来计算,它用位移势表示。在严重的各向异性岩石中,准剪切波有复杂的方向特性,并有歧点。准压缩波偏离各向同性介质中的方向特性较少。这两种波的到达时间与用文献中的公式计算的群速度相符。沿固体对称轴的井充满流体时,井下声测井仪器的响应也用同样的一般方法计算。根据波形可指示出固体的各向异性程度。对剪切波反射测量来说,用简单的合成记录说明了各向异性的一种可能效应。一个在水平平面内有各向异性的地层使剪切波分裂成两个脉冲,因此使深反射复杂化。这个地层本身反射的偏振面发生旋转。因此,激发方向不同的两个剪切波剖面互相比较,应能指出地下水平平面内的各向异性。
The anisotropy of the crustal rocks may be due to fractures, stress range, particles are arranged in a certain direction or fine bedding caused. The finely layered rock can be represented by a transversely isotropic solid whose axis of symmetry is perpendicular to the formation. The wave emitted by a point force in such a medium is calculated by the numerical inversion of the double Fourier transform of the displacement, which is expressed by the displacement potential. In severe anisotropic rocks, quasi-shear waves have complex directional characteristics and divergence. The quasi-compressional wave has less directional characteristic in the isotropic medium. The arrival time of these two waves corresponds to the group velocity calculated using the equations in the literature. When the well along the solid axis of symmetry is filled with fluid, the response of the downhole acoustic logging tool is also calculated using the same general method. According to the waveform can indicate the degree of anisotropy of the solid. For shear wave reflection measurements, a simple synthetic record illustrates one possible effect of anisotropy. A formation with anisotropy in the horizontal plane splits the shear wave into two pulses, thus complicating deep reflections. The plane of polarization reflected by this formation itself is rotated. Therefore, comparing two shear wave profiles with different excitation directions, we should be able to point out the anisotropy in the horizontal horizontal plane.