Greenstone belt
Greenstone belts are zones of variably metamorphosed mafic to ultramafic volcanic sequences with associated sedimentary rocks that occur within Archaean and Proterozoic cratons between granite and gneiss bodies.Through time, the degree of sediment contained within greenstone belts has risen, and the amount of ultramafic rock (either as layered intrusions or as volcanic komatiite) has decreased.Archaean plate tectonics did not take place on mature crust and as such the presence of thrust-in allochthonous greenstone belts is expected.By the Proterozoic, magmatism was occurring around cratons and with established sedimentary sources, with little recycling of the crust, allowing preservation of more sediments.Proterozoic greenstones occur sandwiched between the Pilbara and Yilgarn cratons in Australia, and adjoining the Gawler Craton and within the extensive Proterozoic mobile belts of Australia, within West Africa, throughout the metamorphic complexes surrounding the Archaean core of Madagascar; the eastern United States, northern Canada and northern Scandinavia.
metamorphosedultramaficvolcanicsedimentary rocksArchaeanProterozoiccratonsgranitegneissmineralschloriteactinoliteamphibolessilvercoppercratontectonicmetamorphicbasaltspillow lavaisland arcterranesbasaltlayered intrusionskomatiiteperidotitePhanerozoicophioliteplate tectonicsthrust-inallochthonousmagmatismrecycling of the crustmetabasaltgreenschistwhiteschistblueschistArcheanstratigraphic columnpyroclasticsfelsicandesiteclasticstholeiiticCalc-alkalineTemagami greenstone beltCanadian ShieldSlave cratonCanadaPilbara cratonYilgarn CratonWestern AustraliaGawler CratonSouth AustraliaWyoming CratonKaapvaal cratonMadagascarWest AfricaBrazilScandinaviaKola PeninsulaBaltic Shieldeastern United StatesAbitibi greenstone beltOntarioQuebecFisher MassifBarberton greenstone beltSouth AfricaUniversity of the WitwatersrandJohannesburgpillow lavasspinifexcrystalsList of greenstone beltsGiyani Greenstone BeltDharwar CratonCentral Lapland Greenstone BeltBird River greenstone beltFlin Flon greenstone beltHope Bay greenstone beltKivalliq RegionNunavutHunt River greenstone beltIsua greenstone beltNuvvuagittuq greenstone beltRattlesnake Hills greenstone beltSeminoe Mountains greenstone beltSouth Pass greenstone beltYellowknife greenstone beltEconomic GeologyBibcodeAustralian Antarctic DivisionPrecambrian ResearchGeologyAbitibiBarbertonBird RiverCentral LaplandEcstallFlin FlonHope BayHunt RiverNuvvuagittuqRattlesnake HillsRed LakeSeminoe MountainsSouth PassSwayzeTemagamiYellowknife