变延拓步长相移法偏移及其在微机上的实现

PHASE-SHIFT MIGRATION IN VARIABLE CONTINUATION STEP-LENGTH AND ITS IMPLEMENTATION ON MICROCOMPUTER

河南省地矿厅地球物理勘查队

Geophysical Explanation Party uvder the Henan Bureau of Geology and Mineral Resources

本文讨论了相移法波动方程偏移的原理,对相移插值公式加以改进变形后,给出了一种不同于时间域内插的新的变延拓步长的方法。由于采用了快速矩阵转置,频域变延拓步长及正、余弦函数值造表等方法,因此,程序运行效率及横向道处理能力都有较大的提高,使得在微机上实现的相移法波动方程偏移具有实际的生产意义。

This paper deals in theory with the wave equation migration by using the phase-shift method. Having had the phase -shifted interpolation formula modified, a new variable continuation step-length being different from the interpolation in time domain is given. As a result of taking approaches, such as the fast matrix conversion, variable continuation step-length in frequency domain, tabulation of sine and cosine function value etc., the programme running effe-ciency and processing capability for lateral traces have been raised considerably. And thus it is deemed significant in implementing the wave equation migration using the phase-shift method on microcomputer, which is proved obviously advantageous to the routine operations.