L-Q-T坐标下的P波与S波接收函数联合反演

接收函数分析是一种研究壳幔结构的主要技术手段。然而, 沉积层引起的多次波会影响壳幔结构特征的可靠研究。与常规Z-R-T坐标下提取接收函数不同, 本文尝试在L-Q-T坐标下提取P波与S波接收函数, 并将二者进行联合反演。通过正演模拟讨论了沉积层厚度对接收函数的影响和实例分析位于具有巨厚沉积的渭河盆地和河套盆地的两个台站, 验证了L-Q-T坐标下提取的P波接收函数能有效显示浅部地壳信息(如沉积层转换波信号), 而P波与S波接收函数联合反演能够有效压制沉积层引起的多次波信号。显示了联合反演方法更具优势, 除能获得界面深度信息, 还能获取速度信息。

Joint Inversion of P-wave Receiver Functions and S-wave Receiver Functions Based on the L-Q-T Coordinate System

Receiver function analysis is a routine method for studying crustal and upper mantle structures. However, sedimentary multiples can negatively impact the accurate determination of crustal and upper mantle structures. In this study, we retrived the receiver functions based on the L-Q-T coordinate system. Then, we conducted joint inversion of P-wave receiver functions (PRFs) and S-wave receiver functions (SRFs) to prove the advantages of this method by providing the case studies of Weihe graben and Hetao graben as well as the illustrative case of the forward modeling results. Our results, on one hand, proved that the L-Q-T coordinate system can present shallow converted crustal signals (e.g., the converted signal of the sedimentary layer), and on the other hand, supported the fact that the simultaneous inversion method was more advantageous for suppressing sedimentary multiples for the more accurate determinantion of the crustal and upper mantle structures.