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Archean of Greenland and Fennoscandia
Pentti,Hoelttae,Victor,Balagansky,Adam,Garde,Satu,Mertanen,Peltonen,Alexander,Slabunov,Peter,Sorjonen-Ward,Martin,Whitehouse +14 more
- Vol. 31, Iss: 1, pp 13-19
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TLDR
The North Atlantic craton in southern West Greenland mainly consists of a tectonic collage of Mesoarchean continental crustal terranes, which were amalgamated at c. 2.7 Ga and are currently exposed at mid-crustal amphibolite to granulite facies levels.Abstract:
The North Atlantic craton in southern West Greenland mainly consists of a tectonic collage of Mesoarchean continental crustal terranes, which were amalgamated at c. 2.7 Ga and are currently exposed at mid-crustal amphibolite to granulite facies levels. Tonalitic orthogneisses predominate, intercalated with slightly older tholeiitic to andesitic metavolcanic rocks and associated gabbro-anorthosite intrusive complexes. The North Atlantic craton also contains enclaves of Eoarchean, c. 3.86-3.6 Ga orthogneisses and supracrustal rocks including the Isua greenstone (or supracrustal) belt. This is the oldest known assemblage of rocks deposited at the surface of the Earth, comprising mafic pillow lavas, banded iron formations and metasedimentary schists with local disseminated graphite of possible biogenic origin. Eoarchean rocks have not been found in Kola and Karelia in Fennoscandia where most rocks are 2.9-2.7 Ga tonalitic-trondhjemitic- granodioritic orthogneisses with intercalated coeval greenstone belts and amphibolites. Mesoarchean 3.0-3.2 Ga rocks are found in the eastern and western parts of the Karelian province. Subduction-related rocks like the Iringora supra-subduction type ophiolite and basalt-andesite-dacite-rhyolite series volcanic rocks in many greenstone belts, as well as eclogites are found in the Archean of Fennoscandia. A clear distinction between Greenland and Fennoscandia is the abundance of 2.75-2.65 Ga igneous rocks in Fennoscandia which indicates that these two cratons had a separate evolution during the Neoarchean.read more
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Baltica, Amazonia and the SAMBA connection—1000 million years of neighbourhood during the Proterozoic?
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Correlation of Archaean and Palaeoproterozoic units between northeastern Canada and western Greenland: constraining the pre-collisional upper plate accretionary history of the Trans-Hudson orogen
TL;DR: In this article, the early, upper plate history of the Trans-Hudson orogen was characterized by a number of accretionary-tectonic events, which led to the nucleation and growth of a northern composite continent (the Churchill domain), prior to terminal collision with and indentation by the lower plate Superior craton.
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Geochronological, geochemical and isotopic study of detrital zircon suites from late Neoproterozoic clastic strata along the NE margin of the East European Craton : implications for plate tectonic models
TL;DR: In this article, detrital zircon suites from Neoproterozoic siliciclastic rocks from the northeast periphery of the East European Craton are used to assess the provenance of sediments and test tectonic models for the late Precambrian assembly of continents.
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Rare earth element distribution and mineralization in Sweden: An application of principal component analysis to FOREGS soil geochemistry
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Single-grain zircon U–Pb age constraints of the western and eastern sanukitoid zones in the Finnish part of the Karelian Province
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References
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TL;DR: In this paper, it was shown that a craton with three to four rifted margins has a ca. 10% maximum probability of correlating with any of the ca. 35 remaining Archean cratons around the globe.
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13C-Depleted carbon microparticles in >3700-Ma sea-floor sedimentary rocks from west greenland
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Assigning Dates to Thin Gneissic Veins in High-Grade Metamorphic Terranes: A Cautionary Tale from Akilia, Southwest Greenland
TL;DR: A granodiorite from Akilia, southwest Greenland, previously suggested to date putative lifebearing rocks to greater than or equal to 3.84 Ga, is re-investigated using whole-rock major and trace-element geochemistry, and detailed cathodoluminescence image-guided secondary ion mass spectrometer analyses of zircon U-Th-Pb and rare earth elements.
Book
Precambrian geology of Finland : key to the evolution of the fennoscandian shield
TL;DR: In this article, the results from modern geological and geophysical research are combined into a detailed petrologic, lithologic, and structural synthesis and interpretation of the Archean and Proterozoic of Finland.
Short-lived mantle generated magmatic events and their dyke swarms: The key unlocking Earth's paleogeographic record back to 2.6 Ga
Wouter Bleeker,Richard E. Ernst +1 more
TL;DR: Bleeker et al. as discussed by the authors proposed a new and detailed Superior-Hearne-Karelia reconstruction forming the core of 2.7-2.1 Ga supercraton Superia.