Results 31 to 40 of about 59,536 (124)
Abstract Detailed geochronological, geochemical, and paleomagnetic studies of mafic dyke swarms, often associated with mantle plumes, can provide unique constraints on paleogeographic reconstructions. Mafic dykes with baddeleyite U–Pb ages of 1,233 ± 27 Ma (SIMS), 1,206.7 ± 1.7 Ma (TIMS), 1,214.0 ± 4.9 Ma (TIMS), and 1,236.3 ± 5.4 Ma (TIMS) have been ...
Chong Wang +7 more
wiley +1 more source
Triplite and wolframite from a greisen-bordered veinlet in Eurajoki, SW Finland [PDF]
Triplite and wolframite are described from a greisen-bordered veinlet associated with the local varieties of the Laitila rapakivi granite massif. The chemical analysis, unit cell dimensions and specific gravity are given for these minerals, and in ...
I. Haapala, P. Ojanperä
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Fluid inclusions in cavity quartz crystals in rapakivi from Luumäki, southeastern Finland [PDF]
Fluid inclusions in selected cavity quartz crystals in rapakivi granite from Luumäki, southeastern Finland, were studied by microthermometric methods.
M. Poutiainen
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Crustal development in relation to granitic magmatism in regard to D/H partition between coexisting hornblende and biotite in the Svecofennian belt [PDF]
Tie-lines in the σD-XFe diagram of hornblende and biotite in Japanese island arc granites give commonly a similar slope to that derived from the equation of Suzuoki-Epstein's experimental work (1976).
Y. Kuroda +5 more
doaj +1 more source
REE-bearing minerals in the Rapakavi Grante, Southern Finland
The studied rock samples belong to the classic1615–1645 Ma Wiborg Rapakivi granite terrane of southeasternFinland. Geochemical studies show that the rapakivigranites and associated rocks form metaluminousto peraluminous A-type granites and plot in the ...
Al-Ani Thair
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Th-Rich Zircon from a Pegmatite Vein Hosted in the Wiborg Rapakivi Granite Massif
Zircon from a pegmatite vein hosted in the rapakivi granites occurring in the Gubanov Intrusion of the Wiborg Massif was shown by the EPMA method to contain an anomalously high Th of 18.3 wt% ThO2 (about 161,000 ppm Th).
Sergey G. Skublov +4 more
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Three of the largest granite porphyries of northern Portugal were studied to improve current knowledge on the regional felsic vein hypabyssal magmatism.
Oliveira, António João Teixeira +2 more
doaj +1 more source
The rapakivi granite plutons of Bodom and Obbnäs, southern Finland: petrography and geochemistry [PDF]
The Obbnäs and Bodom granite plutons of southernmost Finland show the typical petrographic and geochemical features of the Proterozoic rapakivi granites in Finland and elsewhere: they cut sharply across the 1900 Ma Svecofennian metamorphic bedrock and ...
P. Kosunen
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Some progress on understanding the Phanerozoic granitoids in China
: There are large volumes of the Phanerozoic granitoid rocks in China and neighboring areas. In recent years, numerous new and precise U-Pb zircon ages have been published for these granitoids, and define many important magmatic events, such as ca.
Tao Wang +8 more
doaj +1 more source
Nature secondary quartzites of the island Bol’shoy Tyuters (Gulf of the Finland, Russia)
Territory Baltic shield is well understood and the identification of innovative geological formations rare stroke of luck. Thanks to the Russian Geographical Society in the summer of 2015 an integrated expedition to study the nature of the little-known ...
Evgenii N. Terekhov +5 more
doaj +1 more source

