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2005
Publisher Summary The Paleoproterozoic Svecofennian bedrock of southern Finland formed during a multiphase convergence and collision of lithospheric plates ∼ 1900 Ma ago. The next event to strongly reshape the Finnish bedrock was the emplacement of the rapakivi granites-∼1600 Ma ago, when the Svecofennian mountain chain had already been eroded down ...
O.T. Rämö, I. Haapala
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Publisher Summary The Paleoproterozoic Svecofennian bedrock of southern Finland formed during a multiphase convergence and collision of lithospheric plates ∼ 1900 Ma ago. The next event to strongly reshape the Finnish bedrock was the emplacement of the rapakivi granites-∼1600 Ma ago, when the Svecofennian mountain chain had already been eroded down ...
O.T. Rämö, I. Haapala
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The pressure quench formation of rapakivi texture
Contributions to Mineralogy and Petrology, 1978Chemical and textural data for rapakivi granites are combined with experimentally determined phase equilibria to provide constraints on the growth of mantled feldspars by a pressure quench mechanism. In water saturated melts of granitic composition the mantled texture develops in response to a decrease in pressure of as little as 1–0.5 kbar.
Cherry, Michael E., Trembath, Lowell T.
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The Soca intrusion: a rapakivi granite of Uruguay
Journal of South American Earth Sciences, 1998Abstract The Soca granite, emplaced in the Rio de la Plata Craton, is located 65 km east of Montevideo. It is a homogeneous porphyritic leucogranite, with almost 75 km 2 of exposed area. Petrographically, the Soca granite is characterized by the occurrence of quartz, plagioclase and alkaline feldspar in two generations, ferrous pyroxene, mica ...
P. Oyhantçabal +3 more
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Metallogeny of the Rapakivi granites
Mineralogy and Petrology, 1995Two major types of ore deposits occur with Proterozoic rapakivi granite plutons: (1) greisen-, vein-, und skarn-type Sn(-W-Be-Zn-Cu-Pb) deposits associated with specialized late-stage granites, and (2) Fe oxide-Cu (-U-Au-Ag) deposits.
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Mineralogy and Petrology, 1994
The dyke-like 1.63 Ga Jaala-Iitti rapakivi complex forms a 25 km long and up to 2 km wide intrusive body at the northwestern margin of the Wiborg rapakivi batholith cutting both the granites of the batholith and the surrounding 1.9 Ga Svecofennian crust.
P. T. Salonsaari, I. Haapala
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The dyke-like 1.63 Ga Jaala-Iitti rapakivi complex forms a 25 km long and up to 2 km wide intrusive body at the northwestern margin of the Wiborg rapakivi batholith cutting both the granites of the batholith and the surrounding 1.9 Ga Svecofennian crust.
P. T. Salonsaari, I. Haapala
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Reduced rapakivi-type granites: The tholeiite connection
Geology, 1997Reduced rapakivi-type granites are the most iron enriched and reduced (i.e., least oxidized) of the “anorogenic” granite association. The low oxygen fugacity and chemical composition of these granites severely limit their sources. In this paper we argue that reduced rapakivi-type granites and their eruptive equivalents, high-potassium fayalite ...
Carol D. Frost, B. Ronald Frost
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The Genesis of the Rapakivi Granites
Geologiska Föreningen i Stockholm Förhandlingar, 1937(1937). The Genesis of the Rapakivi Granites. Geologiska Foreningen i Stockholm Forhandlingar: Vol. 59, No. 4, pp. 503-524.
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Rapakivi granites and related rocks: an introduction
Precambrian Research, 1999Abstract This article is an introductory chapter for the proceedings of the last, seventh, meeting of the International Geological Correlation Programme (IGCP) Project 315 “Correlation of Rapakivi Granites and Related Rocks on a Global Scale”, 1991–1996.
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The Problems of the Rapakivi Granites
The Journal of Geology, 1938The rapakivi granites of Fennoscandia, characterized by Johannsen as "abnormal," include coarse-grained rocks having a peculiar ovoidal texture, controlled by the form of their potassium feldspars, which formerly served to define the whole group. When, however, it was realized that associated with the ovoidal varieties there are related granites having
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Rapakivi granites, South Greenland: hydrothermal alteration of igneous layering
Journal of the Geological Society, 1990Igneous layering is developed in the Proterozoic rapakivi granite suite of South Greenland in an area on the south-easternmost coast of the island of Angnikitsoq. The layering at this locality is unusual in that it is defined by interstitial phases. We suggest that large-scale hydrothermal alteration has converted a fine-grained pyroxene cumulate, in ...
ADRIAN A. FINCH +3 more
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