分偏移距动校正方法的改进

在地震资料处理中，速度分析和动校正对资料品质的影响很大。由于动校正速度是随偏移距变化而变化的，而常规速度分析并没有考虑这一因素，动校正效果往往不是很理想，从而影响资料的叠加和成像效果。分偏移距动校方法是在不同偏移距上采用不同的速度进行动校正。但由于是在不同偏移距组上分别独立进行速度分析和动校正，因此不能将不同偏移距组的同一反射同相轴校正到同一to层位上。这样就需要进行繁琐的后续处理，而且还会降低同相轴的连续性和平滑性。为此，对该方法进行了一些改进，即固定to在不同的分偏移距段进行速度扫描，段与段之间的衔接问题采用平滑处理解决。理论模型分析表明，采取上述改进措施后，动校正效果得到了一定提高，改善了同相轴的连续性和平滑性。

Improvement of offset division NMO

Velocity analysis and normal moveout (NMO) greatly affect the data in seismic data processing. The conventional velocity analysis does not consider the influence of the NMO velocity varying with offset, making the results not ideal, leading to a poor stacking and migration imaging. Offset division normal moveout using different stacking velocities in different offset divisions. The velocity analysis and the dynamic correction in the method are carried out respectively in different offset, making the same reflecting event of different offset group being not able to be corrected to the same t0 layer. Therefore, the followed processing is needed. In addition, the continuity and smoothness of the event will be decreased. For these reasons, this method has been modified to a certain extent, that is, for the same t0, the velocity is scanned in different offsets and the joint between the passages are smoothed. The theoretical model analysis shows that the continuity and smoothness of events are improved by using the modified method.