|
Original Article |
1 1School of Geosciences, Monash University, Melbourne, Vic. 3800, Australia (e-mail: Ian.Buick@sci.monash.edu.au)
2 2Department of Geology and Geophysics, University of Adelaide, Adelaide, S.A. 5005, Australia
3 3Research School of Earth Sciences, Australian National University, Canberra, A.C.T. 0200, Australia
4 4Department of Geology, University of Stellenbosch, Stellenbosch 7600, South Africa
5 5Department of Earth and Marine Sciences, Australian National University, Canberra, A.C.T. 0200, Australia
Until recently it has been widely accepted that protoliths to metasediments of the Harts Range Metamorphic Complex (central Australia) were deposited prior to c. 1.75 Ga and form part of the Palaeoproterozoic Arunta Inlier. However, new sensitive high-resolution ion microprobe U–Pb analyses of detrital zircon, together with recently published data, suggest that they were deposited coeval with c. 545–520 Ma sediments from the adjacent, little metamorphosed Neoproterozoic to Palaeozoic Centralian Superbasin. Protoliths of the Harts Range Metamorphic Complex were deposited in the Irindina sub-basin, an early- to mid-Cambrian rift located between the present-day Amadeus and Georgina Basin remnants of the Centralian Superbasin. Deposition occurred during a widespread and long-lived interval of extension in parts of central Australia associated with eruption of the voluminous Kalkarinji Continental Flood Basalts. The Harts Range Metamorphic Complex was metamorphosed to upper amphibolite- to granulite-facies conditions within c. 40 Ma of deposition of its sedimentary protoliths.
Keywords: SHRIMP, zircon provenance, central Australia, metamorphism, tectonics.
