利用地震层析成象技术确定横向非均匀介质中的速度分布和界面位置
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摘要
本文提出了一种横向非均匀介质中的地震层析成象方法，由地震走时资料确定介质的速度分布和界面位置。计算中采用了参数分离、变阻尼、奇异值分解等技术，方程的解较稳定，且可得到解的分办。除反射波外，该方法还可同时利用分析波的资料。因此，适宜于折射及宽角度反射地震测深剖面的资料处理。数字试验结果表明，在模型内部，该方法能得到可靠的反演结果。在边界附近效果较差，受初始值影响较大。
This paper proposes a new seismotomographic method to determine the velocity distribution and positions of the interfaces in a laterally inhomogeneous medium using seismic travel time data. Due to the applications of parameter separating,variable damping and S. V. D. techniques, the solutions of the equations are quite stable and the resolutionx matrix can be obtained. Reflection data and refraction data can be used simultaneously in the image reconstruction. Therefore, this method is suitable for the data processing of refraction and wide angle reflection profiles.Digital tests of this method show that the results inside the model are reliable. However, the results near the boundaries are not good and seriously affected by the initial values.The data processing of the Renxian-Wuqing DSS profile is taken as an example to illustrate the application of this method.
This paper proposes a new seismotomographic method to determine the velocity distribution and positions of the interfaces in a laterally inhomogeneous medium using seismic travel time data. Due to the applications of parameter separating,variable damping and S. V. D. techniques, the solutions of the equations are quite stable and the resolutionx matrix can be obtained. Reflection data and refraction data can be used simultaneously in the image reconstruction. Therefore, this method is suitable for the data processing of refraction and wide angle reflection profiles.Digital tests of this method show that the results inside the model are reliable. However, the results near the boundaries are not good and seriously affected by the initial values.The data processing of the Renxian-Wuqing DSS profile is taken as an example to illustrate the application of this method.
引文
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