The PI has developed an efficient inversion method applicable to both two and three-dimensional magnetotelluric data called the Rapid Relaxation Inverse (RRI). The method is iterative and approximates horizontal derivatives of the electric and magnetic fields with their values from the previous iteration. Then the inverse problems for the conductivity perturbation beneath each site become uncoupled from each other and closely related to the 1-D problem. The methoda is very fast, and computation time grows only linearly with the number of sites of data inverted. 2-D data for realistic data sets can be inverted on high end technical workstations. This grant supports further work to resolve certain computational difficulties, to work on large 2-D problems and extend the method to realistic 3-D problems.
