1. A computer-implemented method for creating a seismic model of sub-surface formations in a defined 2D or 3D volume of a geological structure comprising: partitioning a velocity model domain representing a subsurface structure of the earth in said defined volume into a plurality of blocks, each block having an associated processing task for processing wave data associated with a shot; receiving, at local storage devices, data representing measurement each wave produced by a shot of a sequence of plural shots; and assigning each partitioned domain block to one or more processing nodes of a distributed processing highly parallel computer device having a plurality of processing nodes interconnected through one or more communication networks; computing, in parallel, using said associated processing tasks operating on said receiver data associated with a shot at each said processing node, contributions of forward wave propagation data and reverse wave propagation data at that node, said reverse wave propagation data computed using a residual data from forward wave propagation data computing; and, using said computed forward wave propagation data and reverse wave propagation data contributions to compute a correction term from which the seismic model is updated.