Palaeoproterozoic basement province in the Caledonian fold belt of North-East Greenland

Palaeoproterozoic and Archaean gneiss complexes in northern Greenland: Palaeoproterozoic terrane assembly in the High Arctic

“…arc complex that is marginally older than that exposed in the IMB to the north of the Sunrise Pynt Strait Belt. These granites, diorites and tonalites match in age ones that occur in the Caledonian basement of North East Greenland (Kalsbeek et al, 1993). Southwards, the southern terrane appears to be dominated by Archaean rocks, including a large anorthosite complex (Nutman, 1984).…”

“…However, progress has been made in recent years to unravel the tectono-magmatic history of Greenland's northern shield exposures through isotope geology. Kalsbeek et al (1993Kalsbeek et al ( , 1999 and Nutman and Kalsbeek (1994) reported on the geochronology of the Precambrian crystalline rocks of North-East Greenland, that form reworked basement inliers within the Caledonian mobile belt (inset, Fig. 1).…”

Early Ordovician to Silurian evolution of exotic terranes in the Scandinavian Caledonides of the Ofoten–Troms area – terrane characterization and correlation based on new U–Pb zircon ages and Lu–Hf isotopic data

“…The apparent homogeneity of the crustal component of the source material to Caledonian igneous rocks in the Uppermost Allochthon of the Scandinavian Caledonides, and the overlap of the isotopic characteristics of this source material with that of the source material to Laurentian magmatic rocks in East Greenland, is strongly indicative of a common source and, probably, palaeogeographic setting for all these rocks. It is worth noting that the model ages from basement rocks in the East Greenland Caledonides have Sm-Nd model ages older than 2.1 Ga (Kalsbeek et al 1993;Thrane 2002), and that the terranes within Laurentia with model ages around 1.70 -1.75 Ga are only found much further to the SW using the present-day geography. At present, we interpret this source to the Caledonian magmatic rocks in the Uppermost Allochthon to be a hidden terrane or, alternatively, associated with known 1.70 -1.75 Ga source rocks from Laurentia, such as the Labradoria terrane in northeastern North America (e.g.…”

Proto-basement in Svalbard

“…at Danmarkshavn), Kalsbeek et al (1993) concluded from Rb-Sr, Sm-Nd and zircon U-Pb data that extending for 900km along the Caledonian belt from Central East Greenland to North East Greenland is a major province of Proterozoic gneisses formed before 1975 Ma, and probably at about 2000 Ma, with evidence of rejuvenation of zircon at about 400Ma around the Silurian Devonian boundary; also the Paleoproterozoic rocks incorporated some Archean material. North of 76" however there is a lack of a supracrustal record.…”