秦皇岛32-6构造高分辨率三维地震资料处理技术研究
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摘要
海上高分辨率三维地震勘探资料的质量取决于野外采集、现场处理、勘探工区的地质条件等诸多因素。本文从资料品质分析入手，对不同海域地层高频衰减进行了对比，发现秦皇岛地区河流相地层比南海LD地区海相地层反射能量弱4～6dB这一规律。秦皇岛地区存在的高频衰减严重、信噪比低、反射系数弱、同相轴不连续、设计采集线距太大等不利因素制约了分辨率的提高。通过试验，调整流程参数，解决了提高速度精度、改善大线距高频DMO响应等影响提高分辨率的关键技术问题。试验分析表明采集因素对资料质量有重大影响，狭长的面元网格导致偏移位移和振幅的严重畸变；偏移距过大使道集中信噪比和分辨率较高的近道减少；电缆深浅与摆动对高频有重要影响并导致三维测线之间一致性差的问题。
The quality of offshore high-resolution 3-D seismic data depends on data acquisition, data processing on the spot, geological condition of prospect and so on. By analysing and comparing the different high frequency attenuations due to formations in different off shore areas, the author has found that seismic reflection energies of river factes formation in off shore Qinhuangdao is 4-6dB weaker than those of marine factes formation in LD area in South China sea. In offshore Qinhuangdao,some unfavourable factors such as severe high frequency attenuation, low signal/noise ratio, weak reflection coefficient, discontinuous seismic event, too big line spacing and so on, restrict the improvement of seismic resolution. The experiment of revising technological process and parameters was made to achieve the improvements of velocity and high frequency DMO response in big line spacing condition,which are significant to seismic resolution amelioration. Experiments led to the conclusions that acquisition factor causes great influence on seismic data quality, that narrow bin grid severely distorts migration displacement and amplitude, that too big offset reduces the near traces which have high signal/noise ratio and high seismic resolution, and that the unstable depth and swing of seismic streamer have important effect on high frequency contents and bring the poor consistency problem of three-dimensional seismic lines.
The quality of offshore high-resolution 3-D seismic data depends on data acquisition, data processing on the spot, geological condition of prospect and so on. By analysing and comparing the different high frequency attenuations due to formations in different off shore areas, the author has found that seismic reflection energies of river factes formation in off shore Qinhuangdao is 4-6dB weaker than those of marine factes formation in LD area in South China sea. In offshore Qinhuangdao,some unfavourable factors such as severe high frequency attenuation, low signal/noise ratio, weak reflection coefficient, discontinuous seismic event, too big line spacing and so on, restrict the improvement of seismic resolution. The experiment of revising technological process and parameters was made to achieve the improvements of velocity and high frequency DMO response in big line spacing condition,which are significant to seismic resolution amelioration. Experiments led to the conclusions that acquisition factor causes great influence on seismic data quality, that narrow bin grid severely distorts migration displacement and amplitude, that too big offset reduces the near traces which have high signal/noise ratio and high seismic resolution, and that the unstable depth and swing of seismic streamer have important effect on high frequency contents and bring the poor consistency problem of three-dimensional seismic lines.
引文
1林继武,刘玉班,张振平,王振华.海上三维资料处理中的几个关键技术问题.石油物探,1990,29(3):1～21
2李庆忠.走向精确勘探的道路,石油工业出版社,1993
3俞寿朋.高分辨率地震勘探,石油工业出版社,1993
2李庆忠.走向精确勘探的道路,石油工业出版社,1993
3俞寿朋.高分辨率地震勘探,石油工业出版社,1993
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