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本文介绍了多震相的层析成像的思路和算法，通过穿透和反射走时可以同时作出２维和３维慢度（速度的倒数）重建。我们分析了在穿透和反射数据中确定速度和深度的不确定性，并认识到深度扰动对反射走时异常比慢度扰动更敏感。由不同波类型所提供的对速度和深度的约束，这个算法实际上减少了在一般反射层析成像在速度和深度之间的不确定性，并且也避免了在穿透层析成像中的不确定问题。线性化反演是通过从反射界面深度由分离速度参数迭代进行的。使用一个快速的２－Ｄ和３－Ｄ射线跟踪算法来计算穿透和反射走时和对幔度及反射界面深度的偏导数。深度和速度都用立方Ｂ样条函数来进行参数化。合成例子表明，当同时考虑穿透和反射时间，层析成像的结果得到改进。这个方法也应用到英国煤炭测量局（ＢｒｉｔｉｓｈＣｏａｌＭｅａｓｕｒｅｓ）沿跨线排列所记录的逆ＶＳＰ数据组。通过使用波形配合技术，用同时确定时间延迟和叠加权，可以自动拾取旅行时间。所观察到的逆ＶＳＰ层析成像可比周围介质具有较低速度的两个断层区域成像。断层的位置由附近的反射测线所确定。本文还讨论了在复杂２－Ｄ和３－Ｄ非均匀各向同性介质中地震射线跟踪方法。界面的几何形状和水平速度场都通过使用非均匀步长立方Ｂ－样条节点?
This paper introduces the idea and algorithm of tomographic imaging of multiphase facies, and can reconstruct 2D and 3D slowness (reciprocal of velocity) simultaneously by penetrating and reflecting travel time. We analyzed the uncertainties in determining velocity and depth in penetrating and reflecting data and realized that depth disturbances are more sensitive to slow-moving perturbations than reflections. The constraints on velocity and depth provided by different wave types actually reduce the uncertainty between velocity and depth in general reflection tomography and also avoid the need for Determine the problem. Linearization inversion is performed by iterating from the separation speed parameter from the reflection interface depth. A fast 2-D and 3-D ray tracing algorithm was used to calculate the partial derivatives of penetration and reflection traveltimes and the depth of mantle and reflection interfaces. Both depth and velocity are parameterized using a cubic B-spline function. The synthesis example shows that tomographic imaging results are improved when both breakthrough and reflection times are taken into account. This method is also applied to the inverse VSP dataset recorded by British Coal Measures along a cross-line. Travel time can be picked up automatically by using waveform blending techniques with simultaneous determination of time delays and overlays. The observed inverse VSP tomography can be imaged with two tomographic regions that have a lower velocity than the surrounding medium. The location of the fault is determined by the nearby reflection line. This paper also discusses seismic ray tracing methods in complex 2-D and 3-D inhomogeneous isotropic media. Is the interface geometry and horizontal velocity field both cubic B-spline nodes using non-uniform steps?