摘要
克希霍夫叠前时间偏移被广泛运用于转换波地震成像领域,该方法具有计算效率高、速度模型易于获取的优点。但是,纵横波速度差使纵波和转换波的成像在时间域不匹配,且克希霍夫偏移也无法较好地处理多次到达和保幅等问题。这里提出一种基于波动方程的转换波叠前深度偏移方法,以改善克希霍夫时间偏移的不足。
Kirchhoff pre-stack time migration has being widely used in the field of converted wave imaging. This method has two advantages,high computational efficiency and acquiring velocity model easily.However,for the velocity discrepancy between P and S wave,the images cannot correspond to each other at temporal domain,and Krchhoff migration cannot handle problems well, such as multi-path,amplitude preservation.In the paper,we introduce a converted wave migration based on wave equation,which supposed to overcome the shortcoming of kirchhoff time migration.
引文
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