The correlation of the geophone time series outputs a volume that is roughly equivalent to the raw data of conventional seismic acquisition. The parallel code to manufacture this output volume is almost running. The road ahead is a long one that will involve velocity estimation, converted wave problems, noise suppression and separation, simultaneous inversion of multiple experiments, and migration- in short: the rest of the field of modern seismic data processing.
Before all of these issues are addressed however, one of the principal problems to be addressed is that of the separation of the direct incident Wave field from that reflected from the free surface. This will be my principal goal in the short term. Some preliminary ideas for this are outlined in Artman (2002a).
Assuming positive results, the next step will be to identify a location and acquisition strategy for SEP to collect its second passive seismic dataset as suggested in Claerbout et al. (1988).