A correlation of Aileron Province stratigraphy in central Australia

Abstract

In the Palaeoproterozoic Aileron Province of central Australia, the ages of detrital zircons in sedimentary rocks help to establish the superposition of major basin packages, and the correlation with similar sediment packages elsewhere in northern Australia. The earliest known sedimentary sequence across the west and north Aileron Province, the Lander Package, contains detritus from a terrane dominated by 1880–1840 Ma crystalline rocks and was intruded by 1820–1800 Ma magmatism. The Killi Killi Formation of the Tanami Region and the Ooradidgee Group of the Tennant Region have similar provenance and depositional timing. Deposition of the Ongeva Package of metamorphosed sedimentary and volcanic rocks in the east Arunta Region was coeval with the 1810–1800 Ma Stafford Event, the Ware Group of the Tanami Region, and the Hatches Creek Group of the Tennant Region. A previously unrecognised sandstone sequence with maximum age ca. 1805 Ma underlies the regional angular unconformity below the Reynolds Range Group and the first thermal event seen to affect the overlying Reynolds Package was the ca. 1590 Ma Chewings Event, 200 Myr later. This permits a range of correlation possibilities for the Reynolds Package and its basal unconformity. The detrital zircon age basis for these correlations is preserved in rocks that were metamorphosed to granulite facies and offers a means of identifying the protoliths of high-grade metamorphic units in a complex polymetamorphic terrane.