当前叠前时间偏移技术已得到大力推广, 然而叠后时间偏移技术由于其计算效率高, 加之在某些地区因信噪比等原因其应用效果甚至优于叠前偏移技术, 因此我们不应该完全抛弃叠后时间偏移方法, 而应针对每个区块的信噪比等实际资料的特点选定合适的偏移方法。文章针对西部某低信噪比区块选取了比较常用的3 种叠后时间偏移方法进行试验, 验证了各偏移方法的优缺点及适用条件, 为如何选取合适的偏移方法提供了可靠的依据。

Currently prestack time migration technology has been extended greatly,while the application result of post stack time migration is even more effective than that of prestack migration because of the high calculation efficiency and low S/N ratio in some place. So the authors consider that post stack time migration should not be abandoned completely but the proper migration methods should be chosen according to the characters of seismic data. Aiming at some western area with low S/N ratio ,three usual methods of poststack time migration are chosen for experiments.The experiments validate the relative merits and applicability conditions of these migration methods and provide reliable reference to how to choose proper migration methods.