双源单缆方式采集的天然气水合物三维地震数据采集脚印分析与压制处理

FOOTPRINT ANALYSIS AND SUPPRESS PROCESSING OF DUALSOURCE AND SINGLE CABLE 3D SEISMIC DATA FOR GAS HYDRATE

在海洋地震资料处理中,由于检波点空间分布不均匀造成的采集脚印现象会影响地震资料成像,特别是对双源单缆方式采集的三维地震数据影响更为明显。通过对海上某区双源单缆方式采集的天然气水合物三维地震数据采集脚印形成原因及特点的详细分析,最终分别在叠前采用子波处理、潮汐、水速校正、面元中心化方法,叠后采用频率、波数域滤波的方法压制采集脚印。通过以上关键技术的应用,提高了双源单缆方式采集的三维地震数据的信噪比和分辨率,采集脚印从时间切片和剖面上均有了明显衰减,而且实现了最大限度的保持振幅、频率、相位属性。为精细刻画、描述地质构造形态和预测天然气水合物储层分布及有利富集区带,提供可靠的地震资料。

In marine seismic data processing, acquisition footprints phenomena caused by uneven distribution of detection points can affect the seismic data imaging, especially for dual-source and single ca- ble 3D seismic data. We studied in this paper the 3D seismic data acquisition footprints and their formation by dual-source single cable. Wavelet processing, tide, water velocity correction, binning centralized method are respectively used in prestack and frequency and wave number domain filtering method in post stack to suppress acquisition footprints. Through the processing mentioned above, we can improve the signal-to-noise ratio and resolution of the dual-source and single cable 3D seismic data, and the acquisition footprints from the time slices and profiles are obvious attenuated. Thus we can keep the maximum amplitude, frequency, phase properties for the seismic data, which are reliable for study of geological tectonics and forecasting of favorable distribution zones of natural gas hydrate reservoirs.