A non‐collisional, accretionary Sveconorwegian orogen

Slagstad, Trond; Roberts, Nick M.W.; Marker, Mogens; Røhr, Torkil S.; Schiellerup, Henrik

doi:10.1111/ter.12001

Cited by 108 publications

(110 citation statements)

References 46 publications

Supporting

Mentioning

106

Contrasting

Order By: Relevance

“…The HBG suite is then interpreted as a function of the subsequent relaxation with gravitational collapse and upwelling of astenospheric mantle, the shorter-lived anorthosite-mangerite-charnockite plutonism indicating melting of dry and reduced lower crust whereas the HBG is attributed to melting of wet and oxidized lower crust (Vander Auwera et al, 2011). The contrasting view advanced by Slagstad et al (2013a) considers the SMB suite instead as a Cordilleran-type, subduction-related, plutonic complex. The post-SMB lull in magmatic activity is attributed to flattening of the slab, with renewed steep subduction and presumably stepping back of the slab causing some delamination and back-arc activity which then produces the HBG suite.…”

Section: Discussionmentioning

confidence: 99%

“…Three main plutonic associations have been recognised: (1) the Sirdal Magmatic Belt (SMB), including the Feda-Fennefoss suite, formed between 1060 and 1020 Ma (Bingen et al, 2008(Bingen et al, , 2015Vander Auwera et al, 2011;Slagstad et al, 2013a;Coint et al, 2015); (2) the hornblende-biotitegranitoid suite (HBG), formed between 990 and 920 Ma (Bingen et al, 2008;Vander Auwera et al, 2011); and (3) the anorthosite-mangerite-charnockite suite formed between 950 and 920 Ma (Schärer et al, 1996;Vander Auwera et al, 2011). The SMB is a calc-alkaline, magnesian association whereas the HBG is more alkaline and ferroan (Slagstad et al, 2013a).…”

Section: Discussionmentioning

confidence: 99%

“…The Precambrian basement of southwestern Norway formed between 1500 and 900 Ma, an evolution concluded by the widespread emplacement of intrusive rocks across the orogen (e.g., Bingen et al, 2008;Slagstad et al, 2013a). The latter are grouped into different suites with different ages, compositional characteristics, and geneses, as elaborated below.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The U–Pb age of the Finse batholith, a composite bimodal Sveconorwegian intrusion

Jensen¹,

Corfú²

2016

NJG

View full text Add to dashboard Cite

The Sveconorwegian autochthonous basement in the Finse area, South Norway, comprises a c. 900 km 2 bimodal batholith, dominated by K-feldspar megacrystic granite. The granite is locally intermingling with gabbroic rocks, and cut by different generations of pegmatite and aplite dykes. Zircon U-Pb geochronological data obtained by ID-TIMS demonstrate that granite, granodiorite and gabbro are coeval, as they define a common upper intercept age of 985.6 ± 1.6 Ma, dating emplacement of the batholith. Titanite is variously disturbed by later Sveconorwegian events. Pegmatites cross-cutting all structures yield zircon and titanite ages of 976 ± 8 Ma, 939 ± 2, and possibly 958 ± 2 Ma, reflecting the latest stages of the evolution of the batholith. The Finse batholith is one of the earliest members of the widespread ferroan hornblende-biotite-granitoid (HBG) suite, in the western part of the Sveconorwegian orogen.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The U–Pb age of the Finse batholith, a composite bimodal Sveconorwegian intrusion

Jensen¹,

Corfú²

2016

NJG

View full text Add to dashboard Cite

show abstract

“…2004;Roberts et al 2011). Early-to late-tectonic Sveconorwegian granitoids intrude the region and are dated between 1.05 and 0.93 Ga (Andersen et al, 2002a(Andersen et al, , 2007aBingen & van Breemen, 1998;Schärer et al, 1996;Slagstad et al, 2012;Vander Auwera et al, 2011).…”

Section: Geological Settingmentioning

confidence: 99%

Sedimentary recycling in arc magmas: geochemical and U–Pb–Hf–O constraints on the Mesoproterozoic Suldal Arc, SW Norway

Roberts

Slagstad

Parrish

et al. 2012

Contrib Mineral Petrol

Self Cite

View full text Add to dashboard Cite

The Hardangervidda-Rogaland Block within southwest Norway is host to ~1.52-1.48 Ga continental building, and variable reworking during the ~1.1-0.9 Ga Sveconorwegian orogeny. Due to the lack of geochronological and geochemical data, the timing and tectonic setting of early Mesoproterozoic magmatism has long been ambiguous. This paper presents zircon U-Pb-Hf-O isotope data combined with whole-rock geochemistry to address the age and petrogenesis of basement units within the Suldal region, located in the centre of the Hardangervidda-Rogaland Block. The basement comprises variably deformed grey gneisses and granitoids that petrologically and geochemically resemble mature volcanic arc lithologies.U-Pb ages confirm that magmatism occurred from ~1521 to 1485 Ma, and conspicuously lack any xenocrystic inheritance of distinctly older crust. Hafnium isotope data range from εHf (initial) +1 to +11, suggesting a rather juvenile magmatic source, but with possible involvement of late Palaeoproterozoic crust. Oxygen isotope data range from mantle-like (δ 18 O ~5‰) to elevated (~10‰) suggesting involvement of low-temperature altered material (e.g. supracrustal rocks) in the magma source. The Hf-O isotope array is compatible with mixing between mantle-derived material with young low-temperature altered material (oceanic crust/sediments) and older low-temperature altered material (continent-derived sediments). This, combined with a lack of xenoliths and xenocrysts, exposed older crust, AFC trends and S-type geochemistry, all point to mixing within a deep-crustal magma-generation zone. A proposed model comprises accretion of altered oceanic crust and the overlying sediments to a pre-existing continental margin, underthrusting to the magma generation zone, and remobilisation during arc magmatism. The geodynamic setting for this arc magmatism is comparable to that seen in the Phanerozoic (e.g. the Sierra Nevada and Coast ranges batholiths), with compositions in the Suldal Sector reaching those of average upper continental crust. As within these younger examples, factors that drive magmatism towards the composition of the average continental crust include the addition of sedimentary material to magma source regions, and delamination of cumulate material. Underthrusting of sedimentary materials and their subsequent involvement in arc magmatism is perhaps a more widespread mechanism involved in continental growth than is currently recognized. Finally, the Suldal Arc magmatism represents a significant juvenile crustal addition to SW Fennoscandia.

show abstract

“…Even for the well-studied East Laurentian region, and its record of interaction with Baltica and Amazonia, a variety of paleogeographic models have been proposed for the configuration and interaction of these cratonic blocks. For example, the Sveconorwegian Orogen in southern Baltica (present co-ordinates) is generally inferred to have formed through continental collision with Amazonia during Rodinia assembly and be contiguous with the Grenville Orogen (Bingen et al, 2008c;Gower et al, 1990;Park, 1992) but recently formation of the orogen in an accretionary setting on the margin of Rodinia has been proposed (Slagstad et al, 2013a). The assembly of Amazonia and Laurentia has been related to both oblique or orthogonal collision, dependent in part on the relative positions of these cratons before and after collision (e.g., Dalziel, 1997;Evans, 2013;Johansson, 2009;Park, 1992;Pisarevsky et al, 2014;Pisarevsky et al, 2003;Tohver et al, 2004b).…”

Section: Introductionmentioning

confidence: 99%