一种改进的近地表强吸收补偿方法研究

摘要

Strong absorption effect posed on seismic wavefield by near surface is very remarkable.Predecessors have developed many ways to reduce the impact and some good compensation effect has been found.If we directly apply the compensation formula which is suitable for solid rock to near surface directly,some technical problems exist,such as unreasonable compensation quantity distribution,difficult parameter optimization.Ideal compensation for near surface absorption can not be reached so far.On the basis of studying previous compensation technology for seismic absorption compensation technology,some existing problems of the original compensation method are analyzed.A correction factor is added in the compensation calculation formula,an improved compensation method for near surface strong absorption compensation method is proposed which are controlled by two factors,gain threshold and frequency threshold.The above existing problems in near surface absorption compensation mentioned above have been ameliorated.Seismic shot records with reasonable compensation for near surface absorption compensation is obtained,so the improved method can be widely used in the compensation processing for the near surface absorption.%近地表对地震波的吸收效应非常强,前人用了很多吸收补偿的方法来减小其影响,虽然取得了一些不错的补偿效果,但将适用于深层成岩地层的补偿公式应用于近地表存在着补偿量分布不合理、运算参数难以优选等技术问题,未达到理想的近地表吸收补偿目的.在研究地震波吸收补偿技术的基础上,分析了常用的补偿方法存在的问题,在补偿因子的计算公式中引入一个修正系数,给出了一种适合近地表强吸收的由增益门限和频率上限双因素控制的补偿方法,解决了以往近地表吸收补偿存在的问题,获得了表层低降速带吸收补偿较为合理的地震剖面.该方法可广泛应用于地震资料的近地表强吸收补偿处理.