克希霍夫叠前时间偏移技术在复杂构造带地震资料处理中的应用

Application of Kirchhoff PSTM to seismic data of complex structure

在辽河盆地东部凹陷中部的A区块地下构造复杂,以往的资料虽然反应了该区的整体面貌,但断裂带的成像效果不是很好,为此,开展了叠前时间偏移处理技术研究.详细介绍了保福克希霍夫叠前时间偏移的原理和数据的预处理,讨论了主要的偏移参数的测试和选取方法,通过Deregowski循环法和百分比偏移扫描速度建立和优化速度模型.处理结果表明,该区三维叠前偏移剖面较常规三维叠后偏移剖面有明显改善.

The area studied is located in the central segment of the eastern subbasin of the Liaohe oilfield. Athough the seismic profile processed before reflects the whole configuration, its imaging effect is not very perfectable. So we develop prestack time migration. We introduce the theory of Kirchhoff PSTM and pre-process steps for PSTM, discussing the primary testing and choice methods of PSTM parameters. We use the Deregowski iterative method and the different percent velocity scanning of PSTM to create and improve the velocity model. The result demonstrates that the method of Kirchhoff PSTM has improved the seismic profile greatly.