Constrained Joint Inversion of Multiple Data Sets for Upper Mantle Velocities in the Southern Rio Grande Rift

We develop high-quality 3-D Earth models by integrating different types of information from a variety of sources and with varying accuracy, sensitivity, and resolution. When incorporating multiple data sources to image the Earth we expect to enhance the ability to answer general and specific questions about the evolution of the Earth and its processes. To this end we propose a novel mathematical approach for joint inversion of multiple geophysical data sets to characterize velocity structure of the upper mantle in the Southern Rio Grande Rift (SRGR) region. This region is of special interest for being one of the major continental Rifts; therefore our understanding of the SRGR activity can help us to analyze evolution processes in other continental Rifts around the world. The joint inversion problem is posed as in nonlinear programming and solved with interior-point methods. We introduce physical bounds over the model parameters and a measure of differences in geological structure. Bound and structural constraints introduced as a priori information to better estimate the physics of each dataset, has shown to improve the numerical results while reducing computational efforts in finding regularization parameters. We will present initial results revealing 3-D velocity structure that suggests continuation of deformation and extension of the Rift.