A long-range seismic profile in Southeastern Australia

Nine portable seismic stations deployed across the Western Plains of New South Wales recorded signals in the distance range 250-1000 km from large timed explosions at both ends of the line. A velocity—depth model derived from the travel-time data has the following features: a two-layer crust with a thickness of 35 km; a sub-Moho velocity of 7.98 km/s; an abrupt increase to 8.36 km/s at 100 km depth; a further step to 8.72 km/s at 190 km depth, with a low-velocity channel immediately above the discontinuity. The model has several features in common with others derived from long-range profiles in Australia and elsewhere. The data, however, provide the first suggestion of a low P-velocity channel in Eastern Australia.