Simultaneous lithofacies inversion from prestack amplitudes

Lithofacies prediction from well and seismic data is the challenge for the oil and gas industry to accurately describe the subsurface geology. This paper describes how lithofacies represented by probability vectors can be inverted using simultaneously all the amplitudes corresponding to various distances between source and receiver (offset) reflecting on the same interface. The inverse problem is solved using a maximum likelihood approach similar to the one described by Tarantola (1987). Prior information deduced from well is introduced to add high frequency and better conditioning.