Events

Speaker: Shuo Zhang, Postdoctoral Researcher, University of Texas Institute for Geophysics

Host: Mrinal Sen

Title: Spatial and temporal variations of the seismic velocity within the crust of Oklahoma

Abstract: Seismic velocities are essential physical properties for probing the interior structure of the Earth. Benefitting from the widely deployed seismometers, our investigations focus on assessing the spatiotemporal variations in seismic velocity within the crust of Oklahoma. Utilizing full waveform inversion, we construct a 3-D radially anisotropic elastic velocity model for the crust of Oklahoma. The inverted model reveals the spatial distributions of the geological units, as well as the potential geological deformation in the crust of Oklahoma. Additionally, we design synthetic tests to understand the impact of the seismic velocity on the earthquake source parameters. As such, the inverted models provide us an opportunity to re-investigate the induced earthquakes in Oklahoma. Furthermore, we integrate seismic noise cross-correlation functions and sensitivity kernels of coda-wave interferometry to estimate spatial and temporal changes of near-surface seismic velocity (dv/v) in central Oklahoma. Comparisons among dv/v, gravity, and groundwater level suggest a negative correlation between near-surface seismic velocity and terrestrial water storage. Considering higher temporal and spatial resolution, seismometers have potential for monitoring subsurface water distribution and migration.