超大面积三维地震连片叠前时间偏移处理技术在歧口凹陷中的应用

Application of Large Area 3DSeismic Contiguous Pre-stack Time Migration Processing Technology to Qikou Sag

歧口凹陷面积5280km2,地表和地下地质条件都十分复杂。复杂的施工环境所产生的噪音问题、能量和子波复杂变化问题、覆盖次数不均匀问题及地下复杂构造变化所产生的成像问题等,使得"超大面积连片叠前时间偏移处理"工作面临巨大的技术挑战。本文通过分析超大面积三维连片叠前时间偏移处理面临的问题及攻关难点,建立了一整套解决该问题的方案与思路,通过应用叠前多域高频随机噪音的衰减、可控震源子波小相位化处理、连片子波整形、数据规则化处理、WEFOX叠前成像等技术,取得了显著的地质效果,解决了本区勘探面临的诸多问题。

There is about 5280km2in Qikou sag’s area,and there the surface and subsurface geologic conditions are very complex.The noise generated by the complex construction environment,energy and wavelet change complexly,the problem of uneven coverage times and the imaging problem caused by the underground complex structure make it difficult in the work of the contiguous pre-stack time migration processing for a large area.Through analyzing these problems and difficulties,this paper establishes a series of solutions and thoughts and through applying the attenuation technology of pre-stack multi-domain high-frequency random noise,the vibrator wavelet small phase process,the contiguous wavelet shaping,the data normalizing,WEFOX pre-stack imaging technology,it has achieved a remarkable result in geological area and solved many problems in the area of exploration.The results provide an important basis for discovering several hundred million tons of reserves in Qikou sag.