浅层地震资料无畸变动校正

UNDISTORTED DYNAMIC CORRECTION FOR SEISMIC DATA FROM SHALLOW REFLECTORS

成都地质学院物探系

Chengdu college of geology

常规动校正使波形发生拉伸畸变,尤其是浅层更为严重。本文提供了一种无畸变的动校正方法—整体波形正常时差校正(AWNMO),解决了动校正后的波形畸变问题。通过理论模型和实际资料处理表明,不论反射层多浅,动校正后均无畸变现象。该方法容易实现,计算速度快,是用微机处理浅层地震资料理想的动校正方法。实践证明将AWNMO思想用于速度分析,可使浅层地震资料速度谱的质量大大提高。

The stretch distortion often present itself in wave form when conventional dynamic correction is used. Such a phenomenon is clearly seen especially for the data from shallow reflectors. In this papwer ,a technique of dynamic correction without distortion-the ALL WAVEFORM NORMAL MOVEOUT CORRECTION (abbreviated as AWNMO) ,was developed, therefore, the problem of waveform distortion caused by NMO correction could thus be solved. It has been proved by theoretical modelling and data processing that no matter how the reflector is, there is no distortion after the ALL WAVEFORM NORMAL MOVEOUT CORRECTION has been made. Such correction is easy to do and is timesaving,so, it is ideal for carrying out the NMO correction on microcomputer while the shallow seismic data is processed. When it is used in velocity analysis, the quality of the velocity spectrum from the shallow reflectors will also be improved to a great extent,this is also proved by practice.