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Mineralogy and Petrology, 1994
This paper deals with the chemical composition of biotites from rapakivi granites. For this purpose, 61 chemical analyses of biotites from composite anorthosite-rapakivi plutons in the Fennoscandian and Ukranian shields were used. Figurative points of the biotite composition were plotted on diagrams designed for biotites byFoster (1960),Winchell (1949)
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This paper deals with the chemical composition of biotites from rapakivi granites. For this purpose, 61 chemical analyses of biotites from composite anorthosite-rapakivi plutons in the Fennoscandian and Ukranian shields were used. Figurative points of the biotite composition were plotted on diagrams designed for biotites byFoster (1960),Winchell (1949)
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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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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 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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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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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 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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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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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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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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