2008 Alum

Lennox Thompson

Lennox Thompson

Years participated in RESESS:
2006 →
2007 →

An Overview

Seismic Investigation of the Southern Rio Grande Rift

Academic Affiliation: Graduate Student, University of Texas at El Paso, Geophysics
Science Research Mentor: Aaron Velasco – University of Texas at El Paso
Writing and Communication Mentor: Laura Serpa - University of Texas at El Paso


An upwelling of basaltic magma 29 million years ago caused the earth’s crust to spread apart and create a region known today as the Rio Grande Rift (RGR). The RGR extends from central Colorado through New Mexico to northern Mexico near El Paso. The RGR has different geologic features that distinguish it from most other valleys (e.g., RGR was not cut by a river nor does a river branch upstream). A growing body of evidence shows that geologic activity still occurs in the RGR, with a continuation of faulting, seismicity, and widening at a small rate. This research focuses on the Southern Rio Grande Rift (SRGR) to develop a contour map of velocity structures and moho depth using data from seismograms that have been installed around the region. The topographic mapping, Vp/Vs ratio, and the crustal thickness of the SRGR will define the crustal structure and the tectonic evolution of the region. The results will assist in understanding the crustal structure of not only the SRGR, but the RGR in general. Results have been obtained for the SRGR using Generic Mapping Tool which includes a contour plot of the Vp/Vs ratio and crustal thickness in that region.