Tectonic framework and evolution of the Gawler Craton, southern Australia

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doi: 10.2113/gsecongeo.102.8.1377
Authors:Hand, Martin; Reid, Anthony; Jagodzinski, Liz
Author Affiliations:Primary:
University of Adelaide, School of Earth and Environmental Sciences, Adelaide, South Aust., Australia
University of Tasmania, Australia
PIRSA, Geological Survey Branch, Australia
Volume Title:special issue devoted to Proterozoic iron oxide Cu-Au-(U) and gold mineral systems of the Gawler Craton
Volume Authors:Skirrow, Roger G., editor; Davidson, Garry J.
Source:A special issue devoted to Proterozoic iron oxide Cu-Au-(U) and gold mineral systems of the Gawler Craton, edited by Roger G. Skirrow and Garry J. Davidson. Economic Geology and the Bulletin of the Society of Economic Geologists, 102(8), p.1377-1395. Publisher: Economic Geology Publishing Company, Lancaster, PA, United States. ISSN: 0361-0128
Publication Date:2007
Note:In English. 104 refs.; illus., incl. 4 tables, geol. sketch maps
Summary:The Gawler craton is the major crustal province in the S Australian Proterozoic and is pivotal in models seeking to describe the evolution of Proterozoic Australia. The craton is host to the Olympic Dam iron oxide Cu-Au-U-REE deposit, as well as a number of other iron oxide copper-gold (IOCG), Au, and iron ore deposits. The evolution of the Gawler craton is dominated by two major phases of tectonic activity, the Late Archaean and late Palaeoproterozoic to early Mesoproterozoic, in total spanning ∼1 billion years. The Late Archaean (2560-2500 Ma) basin development was coeval with arc-like felsic magmatism and mafic-ultramafic magmas, including komatiites. Collisional deformation between 2480 and 2420 Ma led to ∼400 m.y. of tectonic quiescence, conceivably within an early Palaeoproterozoic continental interior. The second major phase of tectonic activity was in the middle to late Palaeoproterozoic and early Mesoproterozoic (2000-1450 Ma). Palaeoproterozoic tectonism was initially dominated by rift-related events; these produced a series of basins over the interval ∼1900-1730 Ma, some of which contain significant iron ore reserves. Transient contractional deformation at ∼1850 Ma led to batholith-scale granitic magmatism, in part derived from melting of the late Archaean basement. Major basin development was finally terminated by the 1730 to 1690 Ma Kimban orogeny, the effects of which are widespread. Regionally, two distinct mineral systems have been recognized: the Olympic IOGG province in the E part of the craton, and the gold-dominated systems within the central Gawler gold province. The spatial distribution of IOGG versus Au-dominated mineral systems appears to reflect regional variations in crustal composition and Hiltaba Suite petrogeneses. The youngest phase of deformation in the craton is expressed by reactivation of shear zones between ∼1470-1450 Ma and regional cooling. [G.L.B.]
Subjects:Absolute age; Archean; Contraction; Copper ores; Crust; Dates; Deformation; Dilation; Faults; Garnet group; Gawler Range Volcanics; Gold ores; Heat flow; Hiltaba Suite; Ion probe data; Isochrons; Magmas; Magmatism; Mass spectra; Mesoproterozoic; Metal ores; Metallogenic provinces; Mineral deposits, genesis; Mineralization; Neoarchean; Nesosilicates; Orthosilicates; Paleoproterozoic; Plate tectonics; Precambrian; Proterozoic; Rare earth deposits; Reactivation; Rifting; Shear zones; SHRIMP data; Silicates; Sm/Nd; Spectra; Strike-slip faults; Structural controls; Tectonics; Transpression; U/Pb; Upper Precambrian; Uranium ores; Whole rock; Zircon; Zircon group; Australasia; Australia; Eyre Peninsula; Gawler Craton; Olympic Dam Deposit; South Australia; Coober Pedy Ridge; Kalinjala shear zone; Kararan Orogeny; Kimban Orogeny; Saint Peter Suite; Sleafordian Orogeny
Coordinates:S350000 S333000 E1373500 E1345500
Abstract Numbers:08M/1861
Record ID:2008063263
Copyright Information:GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from Mineralogical Abstracts, United Kingdom, Twickenham, United Kingdom
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