Above: Starting model for waveform tomography, obtained by traveltime tomography using the

first break arrivals only (courtesy of Colin Zelt, Rice University)

Above: Final result obtained by frequency-domain, acoustic 2-D waveform tomography, using data

frequencies between 0.8 and 7 Hz.

Above: The true model used in the 2-D visco-elastic forward modelling code. The data, comprising

51 sources and nearly 2800 receivers were distributed prior to the workshop, but the model was not

revealed to participants until after the final result (middle image) was produced.