Seismic Vp & Vs tomography of Texas and Oklahoma with a focus on the Gulf Coast margin.

Abstract

We present new 3D seismic tomography velocity models with data from 326 stations, located in Texas, Oklahoma and New Mexico, which utilized 537 seismic events. Tomography results on the North American (NA) craton show a fast anomaly outlining the southern extent. Around the Southern Oklahoma Aulacogen there is a slow anomaly, which indicates there is abundant heat present. In the Gulf Coast Plains, the NA craton shallows, allowing the ascendance of the asthenosphere. Below the craton the velocity models so a slow anomaly associated with the LAB shear zone. The slow velocity along the coast is attributed to the sediment packages. There is also a high velocity body in central/southeast Texas that has begun to delaminate from the upper crust in the region. The upper mantle structures of the Gulf Coast region suggest that the opening of the Gulf of Mexico was due to a volcanically active rifting event.