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===Gondwanaland and Australia=== A [[geological event]] known as the [[Oenpelli]] Dolerite intrusive event occurred about 1,720 million years ago in western [[Arnhem Land]], in the [[Northern Territory]],<ref>{{cite web|url=https://geoscience.nt.gov.au/gemis/ntgsjspui/bitstream/1/74562/1/EL5893_2008_P_01.pdf|title=Wellington Range Project Northern Territory EL 5893 Relinquishment Report|publisher=Cameco Australia Pty Lt|date=August 2008 |series=Report No.: WR08-02 |first1=Cath |last1=Ranford |first2=Paul|last2= Melville |first3=Craig|last3= Bentley|access-date=5 Oct 2020}}</ref> forming curved ridges of Oenpelli Dolerite stretching over {{convert|30,000| km2}}.<ref>{{cite web | website=Australian Stratigraphic Units Database|publisher= Australian Government. Geoscience Australia | title=Definition card for: Oenpelli Dolerite| url=http://dbforms.ga.gov.au/pls/www/geodx.strat_units.def?strno=14496&stratname=Oenpelli%20Dolerite | access-date=5 October 2020}} [[File:CC-BY icon.svg|50px]] Text was copied from this source, which is available under a [https://creativecommons.org/licenses/by/3.0/au/ Attribution 3.0 Australia (CC BY 3.0 AU)] licence.</ref> Further west, on the northern coast of Arnhem Land, a "subsurface radial dyke swarm" known as [[Galiwinku]] Dolerite, taking its name from the [[Aboriginal Australian|Aboriginal]] name for Elcho Island, occurs on the [[Gove Peninsula]] and continues under the [[Arafura Sea]] and on [[Wessel Islands]], including Elcho and [[Milingimbi Island]]s.<ref>{{cite web | website=Australian Stratigraphic Units Database|publisher= Australian Government. Geoscience Australia | title=Definition card for: Galiwinku Dolerite| url=http://dbforms.ga.gov.au/pls/www/geodx.strat_units.def?strno=77145&stratname=Galiwinku%20Dolerite | access-date=5 October 2020}} [[File:CC-BY icon.svg|50px]] Text was copied from this source, which is available under a [https://creativecommons.org/licenses/by/3.0/au/ Attribution 3.0 Australia (CC BY 3.0 AU)] licence.</ref> In the [[Yilgarn craton]] of [[Western Australia]], a [[Proterozoic]] {{convert|200| km |adj=on}} long dolerite dike, the [[Norseman-Wiluna greenstone belt]]<ref>Hill R.E.T, [[Sarah-Jane Barnes|Barnes S.J.]], Gole M.J., and Dowling S.E., 1990. Physical volcanology of komatiites; A field guide to the komatiites of the Norseman-Wiluna Greenstone Belt, Eastern Goldfields Province, Yilgarn Block, Western Australia., Geological Society of Australia. {{ISBN|0-909869-55-3}}</ref> is associated with the non-alluvial [[gold]] mining area between [[Norseman, Western Australia|Norseman]] and [[Kalgoorlie]], which includes the largest gold mine in Australia,<ref>{{cite journal|doi=10.1144/1467-7873/07-132|author1=O'Connor-Parsons, Tansy |author2=Stanley, Clifford R. |title=Downhole lithogeochemical patterns relating to chemostratigraphy and igneous fractionation processes in the Golden Mile dolerite, Western Australia|year=2007|journal=Geochemistry: Exploration, Environment, Analysis|volume=7|issue=2|pages=109–27|bibcode=2007GEEA....7..109O |s2cid=140677224 }}</ref> the [[Super Pit gold mine]]. West of the Norseman–Wiluna Belt is the [[Yalgoo-Singleton greenstone belt]], where complex dolerite dike swarms obscure the volcaniclastic sediments.<ref>{{cite journal|author1=Wanga Q. |author2=Campbella I. H. |year= 1998|title= Geochronology of supracrustal rocks from the Golden Grove area, Murchison Province, Yilgarn Craton, Western Australia |journal=Australian Journal of Earth Sciences|doi=10.1080/08120099808728413|volume=45|issue=4|pages=571–77|bibcode = 1998AuJES..45..571W }}</ref> Large dolerite sills such as the Golden Mile Dolerite can exhibit coarse-grained texture, and show a large diversity in petrography and geochemistry across the width of the sill.<ref name="Travis_etal_1971">{{Citation|last1=Travis|first1=G.A.|last2=Woodall|first2=R.|last3=Bartram|first3=G.D.|chapter=The Geology of the Kalgoorlie Goldfield|editor-last=Glover|editor-first=J.E.|title=Symposium on Archaean Rocks|pages=175–190|publisher=Geological Society of Australia (Special Publication 3)|date=1971}}</ref> The vast areas of mafic volcanism/[[plutonism]] associated with the [[Jurassic]] breakup of the [[Gondwana]] supercontinent in the [[Southern Hemisphere]] include many large diabase/dolerite sills and dike swarms. These include the [[Karoo]] dolerites of [[South Africa]], the [[Karoo-Ferrar|Ferrar Dolerite]]s of [[Antarctica]], and the largest of these, the most extensive of all dolerite formations worldwide, are found in [[Tasmania]]. Here, the volume of [[magma]] which intruded into a thin veneer of [[Permian]] and [[Triassic]] rocks from multiple feeder sites, over a period of perhaps a million years, may have exceeded 40,000 cubic kilometres.<ref>[[David Leaman|Leaman, David]] 2002, "The Rock that Makes Tasmania", Leaman Geophysics, {{ISBN|0-9581199-0-2}} p. 117.</ref> In Tasmania, dolerite dominates much of the landscape, particularly alpine areas, with many examples of [[columnar jointing]]. [[Early Jurassic]] activity resulted in the formation of [[Prospect dolerite intrusion|dolerite intrusion in Prospect]] in [[Sydney]],<ref>Jones, I., and Verdel, C. (2015). Basalt distribution and volume estimates of Cenozoic volcanism in the Bowen Basin region of eastern Australia: Implications for a waning mantle plume. Australian Journal of Earth Sciences, 62(2), 255–263.</ref> and [[quarrying]] of [[basalt]] for [[roadstone]] and other building materials has been an important activity there for over 180 years.<ref name="Johnson1989">{{cite book|author=Robert Wallace Johnson|title=Intraplate Volcanism: In Eastern Australia and New Zealand|url=https://books.google.com/books?id=4NBOn7ecZeAC&pg=PA4|date=24 November 1989|publisher=Cambridge University Press|isbn=978-0-521-38083-6|pages=4–}}</ref><ref>Wilshire, H.G. (1967) The Prospect Alkaline Diabase-Picrite Intrusion New South Wales, Australia. Journal of Petrology 8(1) pp.97-163.</ref>
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