Imaging underground structure using receiver function for P‐S converted waves

Abstract

Receiver function analysis is known as a method frequently practiced to utilize both vertical and horizontal components of seismic records to reveal subsurface structure using earthquake signals in natural seismology. In the receiver function analysis, a receiver function is estimated by the deconvolution of P‐SV horizontal record with the vertical component. This receiver function is used to measure the phase delay of P‐SV converted against P‐P waves. Finally, the phase delay tells the depth of an interface that caused P‐SV conversion. It is obvious that the receiver function analysis is a method based on ray‐theory for a horizontally stratified earth model. We tried to expand the methodology to an imaging tool to utilize the advantage of the receiver function analysis to use both P and SV waves recorded by tri‐component geophones. Also, our modification makes it possible to use not only earthquake records but also artificial signals generated by active sources. We found that the method of receiver function can be extended as a general exploration method for imaging underground geological or geophysical interfaces that causing P‐SV mode conversion in traveling seismic waves.