A self-adaptive algorithm for choosing reference velocities in the presence of lateral velocity variations

Based on perturbation theory, the wave equation extrapolation operator with mixed domains has the ability to deal with lateral velocity variations. It is the image method that has undergone much research in seismology. All extrapolation operators face the problem of choosing the reference velocity due to continuation in depth. The wavefield extrapolation operator with a single reference velocity is suitable for media with weak lateral variation. The multi-reference velocity extrapolation operator can cope with severe lateral velocity variations and improve image accuracy. However, the calculation cost is large. We present a self-adaptive approach to automatically determine the number of selected reference velocities according to the complexity of structure and the given velocity threshold value. The approach can be used to construct the SSF, FFD, WXFD, and GSP multi-reference velocity wavefield extrapolation image algorithms. The result of a salt-dome model data test demonstrates that the self-adoptive multi-reference wavefield extrapolation algorithm has the ability to deal with severe lateral velocity variations and can also be used for structure edge detection. The method is flexible and computationally cost-effective.

基于不安理论，有混合的域的波浪方程推测操作符有能力处理侧面的速度变化。是图象方法在地震学经历了许多研究。所有推测操作员面对深入地由于继续选择参考速度的问题。有单个引用速度的波浪领域推测操作符对有弱侧面的变化的媒介合适。多参考速度推测操作员能应付严重侧面的速度变化并且改进图象精确性。然而，计算费用大。我们在场自动地根据结构和给定的速度阀值值的复杂性决定选择引用速度的数字的一条自我适应的途径。途径能被用来构造 SSF， FFD， WXFD，和 GSP 多参考速度波浪领域推测图象算法。咸屋顶的模型数据测试的结果证明自我采纳的多参考波浪领域推测算法有能力处理严重侧面的速度变化和罐头也被用于结构边察觉。方法是灵活的并且计算联盟者划算。