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Presence of multiples leads to poor quality in main stages of offshore seismic data processing, such as velocity analysis, stacking and imaging. Three basic multiple attenuating methods are reviewed; and a more effective multiple attenuator is achieved by joining them. As the first step, shot or receiver records are extrapolated by wave-equation datum algorithms. The extrapolation will establish a model of waterbottom multiples. Waterbotton multiples will then be removed by subtracting the extrapolated records from the original records. After that, predictive deconvolution is used to attenuate the multiples created by source ghost. Finaly, RADON transformation is adopted to separate peg-leg multiples and residual water-bottom multiples from the original data in the τ-p domain.

地震勘探尤其是海上地震勘探中存在着各类多次波，由于多次波的存在严重影响了速度分析、叠加、偏移成像等地震资料处理，海上多次波主要有全程多次波和层间多次两大类，为了压制海上不同类型的多次波，本文首先分析波场外推、预测反褶积和拉东变换衰减不同多次波的理论基础，然后联合采用这些方法，分别衰减全程多次波和层间多次波；即：首先对炮记录或者接收点记录进行波场外推，建立海底多次波模型，预测并减去全程多次波，然后利用预测反褶积衰减掉周期性明显的多次波，最后将数据转换到τ-p 域，用拉冬变换根据同一时间多次波和有效波在速度等方面的差异，进一步分离层间多次波和剩余的全程多次波，并在该域中切除分离出的多次波，从而实现联合多次波衰减处理。

Who? I never heard of him, Paul said, before asking teammate James Posey if he had heard of him.

赛后，科比说，他一直都是一名非常出色的射手，今天他打得很棒。

When I joined the company, I rotated around the different sections.

我加入这个公司时，轮换过几个不同的部门。