Evidence Of Active Rifts In The Southwest United States Using Geophysical Inversion Of Seismic Data

A continental rift represents a zone where the lithosphere has become thinner due to extensional forces associated with plate tectonics. Many of these rifts are still active, such as the East Africa rift, while others appear to be failed rifts. I build upon recent results of crustal structure for the southern section of the Rio Grande Rift using seismic data collected by USArray stations, and extend the analysis into the states of New Mexico, Oklahoma, Arkansas, and Louisiana to investigate the differences between active and failed rifts in the state of Texas. I collect two geophysical data sets, including receiver functions and surface waves, to perform a joint inversion to determine 1-D S-wave velocity structure. Receiver functions and surface wave dispersion are calculated using Earthscope USArray data from stations in the mentioned states. I use a joint inversion based on constrained optimization that introduces a structural constraint over the inversion model. From the 1-D models, I interpolate layers of the S-wave velocity to create a 3-D velocity model. These results allow me to analyze and locate any possible active or failed rifts in the state of Texas. These results are correlated with geophysical data from the states of New Mexico, Oklahoma, Arkansas, and Louisiana