西沙海域天然气水合物地震资料高密度双谱速度分析技术探讨

基于南海西沙海域天然气水合物二维高分辨率多道地震数据资料,使用Geovation地震资料处理系统的高密度双谱速度分析方法进行处理。在叠前时间偏移处理后的道集基础上,进行高密度双谱非双曲线型NMO自动拾取,最终获得解决各向异性问题后的叠前时间偏移剖面。分析结果表明,高密度双谱速度分析技术实现了速度逐道逐点的自动拾取,提高了时间方向的分辨能力、空间方向的分析密度,可以充分挖掘水合物地震数据的潜力。高密度双谱速度分析方法在提高处理质量的同时,可以帮助判定水合物的富集层位,研究似海底反射层附近的详细速度结构,为西沙海域水合物地震资料综合解释提供依据。

HIGH-DENSITY BISPECTRAL VELOCITY ANALYSIS ON GAS HYDRATES SEISMIC DATA PROCESSING IN CHINESE MARITIME XISHA, SOUTH CHINA SEA

Based on 2-dimentional high-resolution multichannel seismic data, we discussed the application of highdensity bispectral velocity analysis with Geovation in Xisha area, South China Sea. After applying high-density bispectral velocity picking by nonhyperbolic moveout, the effect of anisotropy is resolved in the final PSTM profiles. The results show that high-density bispectral velocity analysis obtains velocity data with automatic picking on every point, which improves temporal resolution and spatial density, and taps into the potential of seismic data. High density bispectral velocity analyzing method improved processing quality, and benefited the detection of accumulation horizon of hydrate, and the exploration of detailed velocity structure near the bottom simulating reflections. This method will be helpful to the interpretation on the gas hydrates seismic data in Xisha area.