DEEP SEISMIC PROFILING IN CENTRAL AUSTRALIA

Deep Seismic profiling undertaken in central Australia comprised expanding spread reflection profiling, long-range refraction work and a small-scale three-dimensional refraction survey, as well as the more usual near-vertical incidence reflection profiling. Scismic reflection sections within the Arunta Block in central Australia show abundant northerly dipping events that are interpreted as reflections from dipping faults, many of which are evident in surface geological mapping. The Redbank Deformed Zone, a major thrust feature, has been imaged to depths of at least 30 km and defines a marked change in reflection character. South of the Redbank Zone, steep, northerly dipping reflections are absent; sub-horizontal basement reflections are prevalent below the Southern Arunta Province and Amadeus Basin. Seismic refraction profiles indicate that the crust is more than 50 km thick below both the boundary between the Southern and Central Arunta Provinces and the northern part of the Amadeus Basin. Expanding reflection spreads and a three-dimensional refraction survey have added fine details to the results in regions of special geological interest and include the resolution of complicated velocity variations in the sedimentary rocks of the northern part of the Amadeus Basin and the measurement of anisotropy in the granulites of the Central Arunta Province adjacent to the Redbank Zone. © 1990.