Stratigraphic timing constraints in the Davenport Province, central Australia: A basis for Palaeoproterozoic correlations

Detailed U-Pb isotopic dates for intercalated volcanics, magmatic intrusions, and detrital zircons in clastic sediments, constrain the stratigraphic development of the Davenport Province in central Australia to the period ca. 1860-1800 Ma. Three basin phases were deposited: the Warramunga Formation, unconformably overlain by the Ooradidgee Group of siliciclastic sedimentary rocks and bimodal volcanics after ca. 1840 Ma, followed by the ca. 1820-1800 Ma Hatches Creek Group of bimodal volcanism and accompanying siliciclastic sedimentation. Mafic and felsic intrusions emplaced in lower parts of the stratigraphy are probable subvolcanic feeders to bimodal volcanism in the overlying sequence. Detrital zircon age spectra are dominated by ca. 1880-1840 Ma detritus with a subordinate presence of older Proterozoic and late Archaean components. The younger Hatches Creek Group is distinguished by the sparse presence of juvenile 1820-1800 Ma detritus which is the same age as contemporaneous volcanism. A similar evolution of both stratigraphic ages and zircon provenance is widespread in the Lander and Ongeva Packages of the Arunta Region, where units are now deformed and metamorphosed by later tectonic events, and also in the Tanami Region Killi Killi Formation and Ware Group basin phases several hundred kilometres to the west. Crown Copyright (C) 2008 Published by Elsevier B.V. All rights reserved.