The Fazenda Gavião granodiorite and associated potassic plutons as evidence for Palaeoproterozoic arc-continent collision in the Rio Itapicuru greenstone belt, Brazil

Geochemistry and U–Pb zircon ages of plutonic rocks from the Algodões granite-greenstone terrane, Troia Massif, northern Borborema Province, Brazil: Implications for Paleoproterozoic subduction-accretion processes

“…1A), for example, the Eburnean-Birimian greenstone belts of the West African Craton (e.g., Abouchami et al, 1990;Hirdes and Davis, 2002;Baratoux et al, 2011;Kock et al, 2011), Paleoproterozoic greenstone sequences in the Guyana Shield (Amazonian Craton) (e.g., Vanderhaeghe et al, 1998;Rosa-Costa, 2006;McReath and Faraco, 2006), metavolcano-sedimentary sequences of São Luis Craton (e.g., Klein et al, 2005Klein et al, , 2008, and the Rio Itapicuru and Rio Capim greenstone belts in the northern São Franscico Craton (e.g., Silva et al, 2001;Mello et al, 2006;Costa et al, 2011;Oliveira et al, 2011). Tectonic evolution for most of these greenstone terranes starts with early oceanic/back-arc basin development at 2260e2230 Ma (e.g., Abouchami et al, 1990;Silva et al, 2001;Baratoux et al, 2011;Nyame et al, 2013), followed by widespread calc-alkaline/TTG volcanism/plutonism at~2190e2120 Ma, and final continental collision and metamorphism at ca.…”

“…The accretion of early juvenile intra-oceanic arcs to continental margins is a very frequent interpretation for plutonic evolution along these Paleoproterozoic terranes (e.g., Klein et al, 2008;Feybesse et al, 2006;Costa et al, 2011;Oliveira et al, 2011;Baratoux et al, 2011). For example, similar to the Algodões plutonic evolution, in the Ghanaian province (West Africa Craton), early development of 2.25e2.17 Ga juvenile TTG-plutonic rocks was followed by extensive 2.16e2.15 Ga monzonitic (mantle-derived) plutons during arc accretion prior to major collision (Feybesse et al, 2006).…”

“…In the northern São Francisco Craton, the Rio Itapicuru and Rio Capim Paleoproterozoic greenstone belts have been interpreted as intra-oceanic arcs that accreted to paleocontinental margins during the Rhyacian orogeny Oliveira et al, 2011). For example, in the Rio Itapicuru greenstone belt, early~2163e2127 Ma juvenile TTG plutons were interpreted to represent an intra-oceanic arc magmatism, but at~2110e2100 Ma a major change in magma composition took place, represented by late mantle-derived plutons (i.e., syenites, adakites, shoshonitic plutons), probably in response to arccontinent collision (e.g., Costa et al, 2011).…”

Tectonic Settings of Potassic Igneous Rocks

“…6 and 7), and hence these new discrimination methods may be useful in exploration as well as in tectonic and petrogenetic studies (cf. De Min et al 2007;Dawod et al 2010;Costa et al 2011;Torabi 2011;Aliani et al 2013;Torabi et al 2014;Orozco-Garza et al 2013;Abbasi et al 2014;Rao et al 2014;Ghasemi and Rezaei-Kahkhaei 2015;Jiang et al 2015;Liu et al 2015). By identifying those older potassic igneous rocks which have the most favourable tectonic settings, it may be possible to identify, more efficiently, those terranes which have enhanced economic potential for specific styles of mineralization associated with high-K igneous rocks (cf.…”

Potassic alkaline granitoid magmatism in the northern margin of the Tarim Craton: First evidence of a back‐arc extensional environment

“…Potassic igneous rocks include a variety of compositions ranging from shoshonites associated with calc‐alkaline volcanic rocks to ultrapotassic leucitites (Campbell et al, ; Foley & Peccerillo, ; Peccerillo, ). Potassic igneous rocks have been recognized as an important and integral component of magmatism at destructive continental margins (e.g., Abbasi, Manesh, Karimi, & Parfenova, ; Carr, ; Costa, Oliveira, & McNaughton, ; Ding et al, ; Foley & Peccerillo, ; Hari, Chalapathi, Vikas, & Guiting, ; Liu, Jiang, Jia, Zhao, & Zhou, ; Morrison, ; Nabatian et al, ; Orozco‐Garza, Dostal, Keppie, & Paz‐Moreno, ; Rao, Srivastava, Sinha, & Ravikant, ; Rios et al, ; Saunders, Tarney, & Weaver, ; Torabi, ; Yang et al, ). Generally, arc‐related potassic igneous rocks are younger, stratigraphically higher, and erupted further from the suture than less potassic rocks, although there are exceptions (Arculus & Johnson, ).…”