Geophysical Tomography Group

During the years 1985-2000 it made developments in the domain of nonlinear fitting of seismic waveforms.

The team tried to make real-life demonstrations that the methods of inverse theory could be applied to the imaging problem typical of seismic exploration.

The GTG was founded by Albert Tarantola, who authored an influential paper on the inversion of seismic reflection data.

[3] The GTG published work on fully nonlinear waveform fitting is possible on seismic exploration data, using elastic modeling and gradient-based optimization techniques (adjoint methods).

The group's work in Monte Carlo method for waveform fitting is being integrated in present-day developments.

The group's logo reflected its name, but also a famous formula in least-squares optimization: transpose of G times G.
First fully elastic nonlinear waveform fitting of exploration data (vertical seismic profile). From Charara et al., 2000.