Tectonomagmatic evolution of the Sveconorwegian orogen recorded in the chemical and isotopic compositions of 1070–920 Ma granitoids

Lead Isotopes and the Sources of Granitic Magmas: The Sveconorwegian Granite and Pegmatite Province of Southern Norway

“…Subdomain A corresponds to the Bamble Sector of [37], Bamble-Lillesand block of [38], and Bamble lithotectonic unit of [39]. Subdomain B comprises the Telemark and Rogaland-Vest Agder sectors of [37]; Telemark and Hardangervidda-Rogaland blocks of [38] or the Telemark lithotectonic unit of [39]. Subdomain C corresponds to the Kongsberg-Marstrand block of [38], combining the unit variously identified as the Western Segment [40], 'Idefjord Terrane' [41] or Idefjorden lithotectonic unit [39] with the Kongsberg Sector of [37] or Kongsberg lithotectonic unit of [39].…”

“…The SSD is composed of several sub-domains, the definition and naming and significance of which remain controversial e.g., [35,38,39,41]. The definition and naming is not important for the present study, and we therefore subdivide the region of interest into three subdomains denoted A, B and C, as shown in Figure 1.…”

“…The presence of inherited, Palaeoproterozoic zircons in Sveconorwegian granites, and the general geochemistry and radiogenic isotope systematics of late Sveconorwegian granites across the subdomain suggest the presence of older rocks in the unexposed crust that are indistinguishable from late Palaeoproterozoic granitoids of the Transscandinavian Igneous Belt [5,44]. Mafic magmatic events occurred at 1.28-1.26 Ga [53,54] and 1.17-1.14 Ga [55][56][57], and felsic magmatism at 1.21-1.20 Ga [19,20,58], 1.05-1.03 Ga [59], followed by the post-orogenic, A-type granitic magmatism at 1.0 Ga to 0.9 Ga [15,39,45] and intrusion of anorthosite and related rocks of the 950-920 Ma Rogaland Igneous Complex [43,[59][60][61][62]. The rocks of Subdomain A have been overthrust Subdomain B along a SE-dipping, ductile shear-zone [37] that has been dated to 1070 Ma [63].…”

A Comparison of the Mica Geochemistry of the Pegmatite Fields in Southern Norway

“…Two main models exist for the tectonic evolution of the Sveconorwegian orogen: i) Bingen et al, (2008) and Möller et al (2015) suggest that the orogen formed by collision of Fennoscandia and Amazonia, ii), whereas Slagstad et al (2013Slagstad et al ( , 2017bSlagstad et al ( , 2018Slagstad et al ( , 2019 and Granseth et al (2020) suggest that the orogen formed as a result of accretionary processes along the Fennoscandian continental margin. In recent years most studies supports the model proposed by Slagstad et al (2013Slagstad et al ( , 2017bSlagstad et al ( , 2018Slagstad et al ( , 2019 and Granseth et al (2020).…”

“…The granites are late-to post-orogenic and range in age from 1000 Ma to 920 Ma (Granseth et al, 2020). Several authors suggest that the granitic melts formed by heat induced melting caused by mafic underplating (Andersen, 1997;Andersen et al, 2001Andersen et al, , 2007Andersen et al, , 2009Slagstad et al, 2017b).…”