摘要
海上地震勘探主要采用的是气枪阵列震源。震源激发时,会形成气泡效应,这种现象会严重影响地震资料浅层成像效果,尤其是天然气水合物地震资料的分辨率和信噪比。利用PGS-Nucleus软件模拟实际震源远场子波,进而用该远场子波进行子波整形处理,气泡得到了较好的压制。远场子波采集成本巨大,因此,在缺少远场子波的情况下,该方法是一种较好的替代方法,能够在保护有效反射的情况下有效压制气泡效应,提高地震资料的分辨率和信噪比。
The seismic source of air-gun array is often used in offshore seismic exploration.Bubble effect will form when the source is excited.Bubbles will seriously affect the quality of seismic data,especially the signal-to-noise ratio of the seismic survey for NGH(natural gas hydrate).In this paper,the authors attempt to use the software of PGS-nucleus to simulate far-field wavelets,and then utilize them to carry out wavelet shaping processing,so as to effectively suppress the bubble oscillation effect.The acquisition cost of far-field wavelets is huge,so in the absence of far-field wavelets,this method is a good choice,which can effectively suppress the bubble oscillation effect protect the effective reflection and improve the signal-to-noise ratio of seismic data.
引文
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