Refined Proterozoic evolution of the Gawler Craton, South Australia, through U-Pb zircon geochronology

C.M. Fanning; R.B. Flint; A.J. Parker; K.R. Ludwig; A.H. Blissett

doi:10.1016/0301-9268(88)90076-9

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Refined Proterozoic evolution of the Gawler Craton, South Australia, through U-Pb zircon geochronology

C.M. Fanning·R.B. Flint·A.J. Parker·K.R. Ludwig·A.H. Blissett

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Abstract

Through the application of both conventional U-Pb zircon analyses and small-sample U-Pb isotopic analyses, the nature and timing of tectonic events leading to the formation of the Gawler Craton have been defined more precisely. Constraints on deposition of Early Proterozoic iron formation-bearing sediments have been narrowed down to the period 1960-1847 Ma. Deformed acid volcanics, including the economically important Moonta Porphyry, have zircon ages of ∼ 1790 and 1740 Ma. The voluminous acid Gawler Range Volcanics and correlatives to the east were erupted over a short interval at 1592 ± 2 Ma, and were intruded by anorogenic granites at ∼ 1575 Ma. Small-sample zircon analyses proved to be an extremely valuable adjunct to conventional analyses, generally yielding more-concordant data which forced a curved discordia through an upper intercept slightly younger than from a conventional straight-line discordia.

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Precambrian Research Article

Source-reported bounding extent: -34.9424835265532° to -28.70185698962701° latitude; 132.93122492920077° to 137.8807542898237° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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C.M. Fanning, R.B. Flint, A.J. Parker, K.R. Ludwig, A.H. Blissett. 1988. Refined Proterozoic evolution of the Gawler Craton, South Australia, through U-Pb zircon geochronology. https://doi.org/10.1016/0301-9268(88)90076-9

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