Abstract

In the Assam region of northeast India, imaging of the Naga thrust fault suffers both from acquisition related noise and a limited understanding of the thrust-belt geology. In such an area the utility of 2-D traveltime and waveform inversion as supplements to conventional imaging and interpretation processes is demonstrated. First, a smooth velocity model with long wavelength characteristics of the subsurface is estimated through 2-D inversion of first arrival traveltimes. Next, the smooth velocity model is used for depth-migration and interpretation of the thrust fault. The quality of part of the migrated image that is poorly resolved due to processing limitations is enhanced using 2- D waveform inversion