Results of bedrock mapping of the Darby Lake - Arrowsmith River north map areas, central Rae Domain, Nunavut

Abstract

The Darby Lake - Arrowsmith River area, southwest of Pelly Bay and southeast of Chantrey Inlet, is readily divided into three northeast-trending lithotectonic subdomains all of which are dominated by granitoid rocks, but contain uncommon, dispersed remnants of upper greenschist- to amphibolite-facies Archean supracrustal rocks dominated by psammite and semipelite with rare mafic and ultramafic units. Greenschist-facies supracrustal rocks are associated in the northwest and southeast by widespread tonalite, granodiorite, and monzogranite. Along the central axis of the map area, a wide range of moderately to strongly deformed, commonly L>S medium-grained to megacrystic granodiorite to dominant monzogranite tectonite bodies at amphibolite facies, grade into biotite±garnet and biotiteorthopyroxene± garnet-bearing granitoid rocks. These granitoid rocks all contain abundant screens, rafts, and schlieren of tonalite, biotite±garnet±hornblende±sillimanite-bearing metasedimentary rocks, and cospatial metasedimentary metatexite and diatexite. Small cupolas of massive biotite±magnetite monzogranite crosscut these rocks

Diachronous Palaeoproterozoic deformation and metamorphism in the Committee Bay belt, Rae Province, Nunavut: insights from 40Ar–39Ar cooling ages and thermal modelling

“…Understanding of the geology of the central Rae province stems primarily from the results of recent mapping of the CBb (Sandeman et al. , 2001a,b, 2005; Sanborn‐Barrie et al.…”

“…Reworking of D 2 structures at lower metamorphic grade during NE‐directed shortening is manifested by conjugate kink‐ to chevron‐style F 3 folds in the eastern part of the PAG supracrustal belt (Sanborn‐Barrie et al. , 2003), and by upright, gentle NW‐striking F 3 cross‐folds elsewhere in the belt (Sandeman et al. , 2001b, 2005; Sanborn‐Barrie et al.…”

Origin and tectonometamorphic history of the Repulse Bay block, Melville Peninsula, Nunavut: exotic terrane or deeper level of the Rae craton?

“…These sequences include the quartzite, carbonate, and mudstone sequences of the <2.3-2.1 and >1.85 Ga Amer group (Rainbird et al 2010 and references therein), the turbidite and shale-wacke sequences of the <1.897 Ga Penrhyn group (Partin et al 2014 and references therein), the siliciclastic, carbonate, and mafic volcanic sequences of the <2.16 and >1.90 Ga Piling group (Scott et al 2002;Partin et al 2014;Wodicka et al 2014), the quartzite, marble, pelite, and conglomerate rocks of the <2.45 Ga Chantrey group (Sandeman et al 2005;Hinchey et al 2007), and arkose and carbonate rocks of the <2.32 Ga Folster Lake formation (Frisch 1982;Rainbird et al 2010). These sequences have undergone variable amounts of deformation and typically preserve greenschist-to amphibolitefacies metamorphism.…”

Neoarchean high-potassium granites of the Boothia mainland area, Rae domain, Churchill Province: U–Pb zircon and Sm–Nd whole rock isotopic constraintsThis article is one of a series of papers published in this Special Issue on the theme of Geochronology in honour of Tom Krogh.

“…Although dominantly metaluminous in composition, minor peraluminous intrusions comprising two-mica and garnet-biotite granitic rocks are interpreted as being contemporaneous with the metaluminous intrusions (Sandeman et al 2005). Some of the metaluminous granitic plutons have Nd isotopic signatures and inherited zircon cores that indicate interaction with older Mesoarchean basement, whereas other intrusions preserve more juvenile Nd isotopic signatures (Sandeman et al 2005;T. Skulski, unpublished data).…”

“…Recent geochronological studies highlight the occurrence of 2.5 Ga granitoids and *2.37 Ga metamorphism within the Queen Maud block (Schultz et al 2007). Correlative Neoarchean supracrustal belts extend from north of Baker Lake to Baffin Island and include the Woodburn Lake Group, Barclay belt, Prince Albert Group, and Mary River Group (Frisch 1982;Frisch 2000;Zaleski et al 2001;Bethune and Scammell 2003;Skulski et al 2003;Sandeman et al 2005). 2.60 Ga intrusive complexes, all of which were variably reworked in the Paleoproterozoic (Heywood 1961;Frisch 1982;Schau 1982;Carson et al 2004;Berman et al 2005).…”