Results 101 to 110 of about 183 (136)

Late Svecofennian shear zones in southwestern Finland

GFF, 2007
Abstract The bedrock of southwestern Finland is transected by a shear zone network with two dominant directions: ∼E-W and ∼N-S. The shear activity occurred after peak metamorphism and crustal melting at 1840-1810 Ma. The shear zones began to form as a consequence of north vergent oblique continent-continent collision and accommodated the resulting ...
Markku Väisänen, Pietari Skyttä
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The accretionary Svecofennian orogen—insight from the BABEL profiles

Precambrian Research, 2005
Abstract The BABEL profiles B, C, 1–7 form a 1200 km long nearly continuous cross-section through the Svecofennides. The near-vertical marine reflection profiles display a wide range of crustal structures that can be associated with both the accretionary Svecofennian orogeny (1.96–1.75 Ga) and the following Subjotnian and Jotnian rift-stages (1.65–1 ...
Korja, Annakaisa, Heikkinen, Pekka
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Late svecofennian magmatism and tectonism, Åland, Southwest Finland

Precambrian Research, 1987
Abstract The Proterozoic, late-Svecofennian, Group III Granites of Sederholm (Ava, Seglinge, Mosshaga and Lemland) form discrete complexes distributed along a NESW line across the Aland Archipelago in southwestern Finland. They were emplaced (1840-1800 Ma) after cessation of the main Svecofennian orogeny, during the subsequent long period of ...
Fred Hubbard, Nick Branigan
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REE-patterns of some Svecofennian migmatite leucosomes

Geologiska Föreningen i Stockholm Förhandlingar, 1991
Abstract REE-patterns obtained from leucosomes of migmatites found in the southern Svecofennian Domain are of two types: one with (La/Lu)N 10. No systematic differences can be found between migmatite leucosomes and Upper Svecofennian granites from the same area.
Lena Mathiasson, Anders Lindh
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Cooling history and age of magnetization of a deep intrusion: A new 1.7 Ga key pole and Svecofennian-post Svecofennian APWP for Baltica

Precambrian Research, 2019
A paleomagnetic and chronogical study has been performed on the Turinge gabbro-diabase formation and on a cross cutting basic dyke in central Sweden and on the Joulovaara gabbro intrusion in northe ...
Sten-Åke Elming, Paul Layer, Ulf Söderlund   +2 more
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U–Pb geochronological constraints of the late Svecofennian leucogranites of southern Finland

Precambrian Research, 2011
Abstract 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, Irmeli Mänttäri, Matti Vaasjoki, O. Tapani Rämö, Mikko Nironen   +4 more
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The Svecofennian orogen: a collage of microcontinents and island arcs

Geological Society, London, Memoirs, 2006
Abstract Based on an integrated study of geological and geophysical data, a tectonic model for the Palaeoproterozoic evolution of the Svecofennian orogen within the Fennoscandian Shield at the northwestern corner of the East European Craton is proposed.
Annakaisa Korja, Raimo Lahtinen, Mikko Nironen   +2 more
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1.8 Ga Svecofennian post-collisional shoshonitic magmatism in the Fennoscandian shield

Lithos, 1998
Abstract 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, D Konopelko, H Rutanen, S Fröjdö, A.D Shebanov   +4 more
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The Svecofennian Orogen: a tectonic model

Precambrian Research, 1997
Abstract Recent geological studies have provided new concepts concerning the timing of the final break-up of the Archaean craton. Age data on detrital zircons from sedimentary rocks in Sweden and Finland show marked similarities and indicate pervasive homogenization of accumulated material.
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Chronology and geochemistry of late Svecofennian processes in northern Sweden

Geologiska Föreningen i Stockholm Förhandlingar, 1989
Abstract Radiometric and geochemical data have been used to characterize the concluding stages of the Svecofennian orogeny in northern Sweden. U-Pb zirzon ages of 1879±7 and 1858±9 Ma have been obtained from two unfoliated granitoids of the North Svecofennian Subprovince.
Torbjörn Skiöld, Björn Öhlander
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