Multiple Leaking Mode Dispersion Observations and Applications From Ambient Noise Cross-Correlation in Oklahoma

Abstract

Surface wave imaging based on the normal modes extracted via ambient noise cross-correlation has become a popular seismological technique during the last two decades. In addition to normal modes, which occupy most seismic wave energy, leaking modes with much weaker energy can also be obtained from ambient noise cross-correlation. We report the observation of multimodal leaking mode dispersion curves retrieved from the cross-correlation of ambient noise recorded by the LArge-n Seismic Survey in Oklahoma array. The extracted leaking modes are closely related to the guided wave dispersion resulting from the layered P-wave velocity (Vp) structure; hence, these modes can be used to invert the Vp structure. Moreover, the joint inversion of leaking modes and normal modes can not only accurately acquire the Vp structure but also effectively improve the fitness of normal modes from the inversion of only normal modes.