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U–Pb geochronological constraints of the late Svecofennian leucogranites of southern Finland
Precambrian Research, 2011Abstract The ∼500 km long zone of late Svecofennian leucogranites in southern Finland is characterized by felsic, in places migmatitic magmatism that crosscuts older Paleoproterozoic crustal segments. SIMS and ID-TIMS U–Pb isotopic data on zircon and monazite from 15 granite and migmatite samples show that the emplacement of individual leucogranite ...
Matti Kurhila +4 more
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The depositional evolution of the Svecofennian supracrustal sequence in Finland and Sweden
Precambrian Research, 1987Abstract On the basis of six new zircon ages from metavolcanic rocks, together with other isotopic, geophysical and geological data, the chronological and tectono-stratigraphic evolution of the early Proterozoic Svecofennian supracrustal rocks in Finland and Sweden are discussed.
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Chapter 8 Svecofennian supracrustal rocks
2005Publisher Summary A substantial part of the Paleoproterozoic crust of southern and central Finland is characterized by 1.92 Ga turbiditic sedimentary and - 1.90-1.88 Ga arc-type volcanic rocks. Fluvial to shallow-water sedimentary rocks, felsic schists, sedimentary carbonates, black shales, and MORB- and WPL-like basalts are locally also common.
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Calcite and dolomite relations in Svecofennian carbonate rocks
Geologiska Föreningen i Stockholm Förhandlingar, 1962Abstract In this paper, the author summarizes his investigations into the occurence and distribution of dolomite and magnesium-silicate minerals in Svecofennian carbonate rocks. As a result of his investigations, the author has come to the conclusion that it is very probable that dolomite rocks have originated in a prehistoric sea, either by direct ...
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Settings of Meteorite Impact Structures in the Svecofennian Crustal Domain
2005The Svecofennian Domain, located on the western part of the East European Craton, is a uniform crustal segment with an age of the basement of ~1.9 Ga. Together with younger (1.5 – 1.8 Ga) transition zones it occupies an area of ~1.56 × 106 km2. The domain unites shield and platform areas including the submerged Baltic Sea.
Väino Puura, Jüri Plado
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Tectonophysics, 2001
Abstract Volcanic and sedimentary rocks of the Vastervik and Valdemarsvik groups along the southern margin of the 1.90–1.85 Ga south Svecofennian crustal province in Sweden have been migmatised and intruded by granitoids and gabbros during extension (deformation phase D1), at a depth of at least 10 km.
Beunk, F.F., Page, L.M.
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Abstract Volcanic and sedimentary rocks of the Vastervik and Valdemarsvik groups along the southern margin of the 1.90–1.85 Ga south Svecofennian crustal province in Sweden have been migmatised and intruded by granitoids and gabbros during extension (deformation phase D1), at a depth of at least 10 km.
Beunk, F.F., Page, L.M.
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Svecofennian detrital zircon ages—implications for the Precambrian evolution of the Baltic Shield
Precambrian Research, 1993Metasediments intruded by 1.90-1.87 Ga old plutonic rocks form the oldest major Proterozoic crustal component in the Svecofennian Domain of the Baltic (Fennoscandian) Shield. Their NdTDM model ages and conventional multigrain zircon UPb ages between 2.4 and 2.1 Ga have previously been interpreted either as mixing ages between ∼ 1.9 Ga old juvenile ...
Stefan Claesson +3 more
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1.8 Ga Svecofennian post-collisional shoshonitic magmatism in the Fennoscandian shield
Lithos, 1998Abstract At least 14 small (1–11 km across) 1.8 Ga Svecofennian post-collisional bimodal intrusions occur in southern Finland and Russian Karelia in a 600-km-long belt from the Aland Islands to the NW Lake Ladoga region. The rocks range from ultramafic, calc-alkaline, apatite-rich potassium lamprophyres to peraluminous HiBaSr granites, and form a ...
O Eklund +4 more
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Chapter 9 Svecofennian mafic-ultramafic intrusions
2005Publisher Summary Mafic-ultramafic plutonic rocks emplaced during Precambrian orogenic episodes are a poorly defined category of intrusions. This is not only because of the long tectonometamorphic history of such terrains and scarcity of young analogies (deeply eroded oceanic or continental arcs), but also because orogenic emplacement of magmas is ...
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Geochemistry International, 2006
A mechanism is proposed to explain the genesis of biotite-quartz-feldspar plagiomigmatite leucosomes as a consequence of the reaction of an amphibolite protolith with ascending fluid. The model is based on the analysis of the mineralogical and geochemical zoning of plagiomigmatite bodies and their outer contact aureoles.
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A mechanism is proposed to explain the genesis of biotite-quartz-feldspar plagiomigmatite leucosomes as a consequence of the reaction of an amphibolite protolith with ascending fluid. The model is based on the analysis of the mineralogical and geochemical zoning of plagiomigmatite bodies and their outer contact aureoles.
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