Determining Structure and Velocities in the Los Angeles Basin Using Passive Seismic with Dense Oil-Company Arrays

Abstract

In this talk I show that you can use the ambient noise recorded by modern node arrays to measure the near-surface shear-wave velocities, the P-wave velocities down to 3 km depth, and the structural boundaries of the Los Angeles Basin and crust. Correlations between each pair of geophones used in the survey produce a “virtual” source that can be use much like an active source but without the problems associated with a vibrator. Surface waves are used to determine the shallow Vs velocities which are important for seismic hazard. P-waves can be extracted and used to determine the Vp velocities, and autocorrelations produce stacked seismic sections for imaging the structure. Examples will be shown for arrays in Long Beach, Seal Beach, Rosecrans and Santa Fe Springs. In addition, the correlations with the regional earthquake network (SCSN) allows the results to be extended be beyond the original surveys

AAPG Datapages/Search and Discovery Article #90339 ©2019 AAPG Pacific Section Convention 2019, Long Beach, California, April 1-3, 2019