Survey of the Shallow Structure at the Northeastern end of the Wenchuan Earthquake Fault Zone by Artificial Seismic Profiling

Abstract

AbstractThe causative fault zone is sensitive to the post‐seismic stress state. We can get the fault healing process by monitoring temporal variations of seismic wave velocity in the fault zone. In order to learn the shallow structure at the northeastern end of the Wenchuan earthquake fault zone, we carried out the shallow structure survey by artificial seismic sources. The strong shallow reflectors and complex structure produced a complicated wave field and the low signal to noise ratio data. Based on separated surface, reflection and refraction waves by f‐k transform, we imaged the subsurface structure by refraction common middle point imaging, surface wave velocity inversion, and reflection wave stack imaging. An integrated interpretation was done combing the three imagine data and the shallow faults and velocity distribution were given. This work is helpful to post‐seismic emergency monitoring of the earthquake fault zone.