Archean Greenstone Granite Belts

Other rocks that occur in granulite gneiss belts zones of.

Archean greenstone granite belts.

The typical green minerals are chlorite actinolite and other green. Archean dome and keel structure granite greenstone belts metamorphism p t t paths vertical and horizontal tectonics 1. Discovered in 1909 the abitibi has generated over 160 million ounces of gold. Greenstone belts are generally elongate archean to proterozoic terrains comprising intrusive and extrusive mafic to ultramafic igneous rocks felsic volcanics and inter flow or cover sedimentary rocks.

Introduction it is thought that mantle potential temperatures were higher in the archean although how much higher than the present day and whether the mantle was warming during the eoarchean mesoarchean to a high. They are characterized by abundant volcanic rocks that include pillowed subaqueous basalt flows and subaerial and subaqueous volcaniclastic rocks. The name comes from the green hue imparted by the colour of the metamorphic minerals within the mafic rocks. Other articles where greenstone granite belt is discussed.

Magnesian komatiites are for the most part absent however. 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. Precambrian precambrian greenstones and granites. Full text access chapter 10 origin and evolution of archean granite greenstone terranes pages 313 381 download pdf.

Greenstone belts occur sandwiched between regions dominated by granitoids and gneiss greenstones are generally of low to moderate metamorphic grade. Archean granite greenstone belts are important components of ancient cratons and are composed of elongate slivers of volcano sedimentary sequences and tonalite trondhjemite granodiorite ttg suites ranging in age from eoarchean 3 6 ga to end of neoarchean 2 5 ga anhaeusser 2014 furnes et al 2014 manikyamba et al 2015. The volcanic rocks range in composition from komatiites and low k tholeiites to dacites and rhyolites and consist of lava flows sills and stratified tuffs. These so called greenstone belts are the remnants of large volcano sedimentary complexes of archean and proterozoic age.

The abitibi belt canada.