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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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Petrological Features of Korsun'-Novomyrhorod Anorthosite-Rapakivi Granite Pluton
Mineralogical Journal, 2021The Korsun’-Novomyrhorod pluton is the second after the Korosten one in terms of the scale of Proterozoic (1757-1748 Ma) anorthosite-rapakivi-granite magmatism in the Ukrainian Shield. According to geochronological data, pluton was formed as a result of multiple ascending and crystallization of basic to acidic melts.
S.G. KRYVDIK +2 more
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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 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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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 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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Geology and age of the Parguaza rapakivi granite, Venezuela
Geological Society of America Bulletin, 1978The 1,550-m.y.-old Paraguaza granite of the northwestern Guayana Shield in Venezuela represents one of the larger, apparently anorogenic rapakivi intrusive rocks of the world. The massive rapakivi granite intrudes foliated granitic rocks and associated volcanic rocks of trans-Amazonian age in a structural setting transcurrent to the general northeast ...
HENRI E. GAUDETTE +3 more
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Petrology of rapakivi granites in Salmi massif
International Geology Review, 1968Crystallization of rapakivi is accompanied by a progressive decrease in the alkali content of the high-temperature granitic magma and by the concurrent increase in its iron content, during the crystallization of potassium feldspar which is followed by the crystallization of biotite.
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Petrogenesis of the Proterozoic rapakivi granites of Finland
1990The rapakivi granites (1.7 to 1.55 Ga) of southern Finland occur as epizonal batholiths (e.g., the Wiborg, Åland or Ahvenanmaa, Vehmaa, and Laitila batholiths) and stocks cutting the medium- to high-grade metamorphic Svecofennian (1.9 to 1.8 Ga) crust.
Ilmari Haapala, O. Tapani Rämö
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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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