The success of depth imaging projects ultimately depends on the quality of the velocity model, of which the salt geometry is generally thought to be the key component in subsalt studies. Standard workflows have therefore been built to define this geometry, which are implicitly based around the simplifying, but apparently widely pertinent assumption that the velocity in the salt is a known constant. Full Waveform Inversion has proved to be a powerful recent addition to seismic velocity model-building technology. However, its use in salt tectonic contexts has been limited. In this paper we present an application of Full Waveform Inversion to a subsalt imaging study using broadband wide-azimuth seismic data: in addition to expected benefits in refining the sediment velocities, the results help redefine some of the salt-body geometries and challenge the original assumption that the salt velocity in the region is that of pure halite and, indeed, that it is constant. While they are supported by the qualitative uplift in the image, full validating of these preliminary conclusions is the subject of ongoing work.
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