海底地震仪浅海广角探测的数据特征与噪声组合压制--以南黄海OBS2016测线为例

2016年6月在南黄海海域实施了海底地震仪（OBS）的二维深地震探测.本文详细分析了在该次地震探测中获得的浅水水域OBS数据的特征，提出了噪声的组合压制方法.研究表明，浅海水域的OBS数据在系统时间、能量及子波等方面存在明显差异，海底多次波干扰严重、有效频段中陷波问题突出，原始台站记录信噪比低、品质差、大炮检距的有效震相难以识别和拾取.本文提出的噪声组合压制处理技术与流程，主要由基于统计子波反褶积的子波整形、基于多项式插值的t-x域线性噪声压制和采用自动搜索的海底多次波压制等三部分组成.净化处理之后，反射/折射震相的波组特征清晰，信噪比得到有效改善与较大提高，可识别震相的范围较常规处理平均扩大60%以上.本文完善了浅水区OBS数据处理的步骤与流程，将为后续地壳结构研究提供可靠的基础数据，可更好的服务于地壳深地震及油气资源的探测.

Characteristics and noise combination suppression of wide-angle Ocean Bottom Seismography (OBS) data in shallow water: a case study of profile OBS2016 in the South Yellow Sea

A two-dimensional seismic survey was carried out in June 2016 along the east-west direction in the South Yellow Sea. We took the actual data processing of survey line (OBS2016) as an example to analyze the data characteristics in shallow water and the combined suppression method of noise in detail. The study shows that OBS data in shallow water have obvious differences in system time, energy and wavelet, and develop submarine multiple with notch. The signal-to-noise ratio of the original record is low, and a far offset seismic phase (>50 km) is difficult to identify and pick up. The noise combination suppression and processing technology used in this paper are mainly composed of wavelet shaping based on wavelet de-convolution, t-x linear noise suppression based on polynomial interpolation, and seabed multiple suppression using automatic searching. The purification results show the characteristics of the wave group are clear, the signal-to-noise ratio is greatly improved, and the range of recognized seismic phase is larger than that on the conventional records (more 60% on average). OBS data processing steps and processes aiming at the shallow water have been improved in this paper, which will provide reliable basic data for subsequent crustal structural research and better serve the deep crust, oil and gas resources exploration.