Depth phases, pP and sP, of an intraplate earthquake offshore from Arnhem Land, Northern Territory, Australia on 30 September 1992 were recorded on seismographic stations throughout southern Australia and on two stations telemetered to Australia from Antarctica. The computed focal depth is 38.8 (±2.5) km, which is near the crost-mantle boundary, deeper than any other known earthquake in Australia. The near-horizontal principal stress direction, 094°, is similar to that of shallow earthquakes in southwest Australia, but the mechanism has a small dip-slip component in contrast to the predominant thrust mechanism of all past shallow earthquakes that were large enough for mechanisms to have been computed.

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