Results 191 to 200 of about 8,056 (240)

Proterozoic Granitoids of Rajasthan

Journal of the Geological Society of India, 2005
Abstract Two granitoid bodies each from Palaeo-, Meso- and Neo-proterozoic periods have been studied for their chemical, petrological and source characteristics The Proterozoic granitoids are megacrystic as well non-megacrystic with variable effect by tectonometamorphic events The Palaeo-proterozoic granitoids are peraluminous ...
S.K Bhushan, V.K. Chittora
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Ultrametamorphism and granitoid genesis

Tectonophysics, 1977
Abstract A model is presented to explain the geochemical and mineralogical characteristics of granitoids and their inclusions. The product of ultrametamorphism is melt + residuum, both of which may move en masse to the site of crystallization. The nature of the source material can be deduced from studies on the granitoids and their inclusions; based
Allan J.R. White, Bruce W. Chappell
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Tectonic discrimination of granitoids

Geological Society of America Bulletin, 1989
Granitoids as categorized by tectonic environment are (1) island arc granitoids (IAG), (2) continental arc granitoids (CAG), (3) continental collision granitoids (CCG), (4) postorogenic granitoids (POG), (5) rift-related granitoids (RRG), (6) continental epeirogenic uplift granitoids (CEUG), and (7) oceanic plagiogranites (OP).
PAPU D. MANIAR, PHILIP M. PICCOLI
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Metamorphism of Granitoid Rocks

2002
Granitoid rocks comprise granite, alkali-feldspar granite, granodiorite and tonalite. They constitute the largest portion of the continental crust. Granitoid gneisses, commonly migmatites, are in fact the dominant rock type of the continents. Because the main constituents — alkali-feldspar, plagioclase, quartz, biotite, muscovite, hornblende — are ...
Kurt Bucher, Martin Frey
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The behavior of tin in granitoid magmas

Economic Geology, 1992
The spatial and temporal relationship between tin mineralization and granitoid rocks is well documented. A great deal of work, including mineralogic, geochemical, fluid inclusion, and stable and radiogenic isotope studies, has been undertaken on numerous cassiterite-bearing deposits in order to resolve the problem of their genesis.
Jeff R. Taylor, Vic J. Wall
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The Granitoid Series and Mineralization

1981
Abstract Granitoids can be classified into either a magnetite-bearing magnetite series or a magnetite-free ilmenite series, a classification also applicable to their effusive equivalents. Magnetite series granitoids are associated with major sulfide mineralization, whereas ilmenite series granitoids are related to cassiterite and ...
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Dike transport of granitoid magmas

Geology, 1993
Thermal and fluid-dynamical analyses suggest that for viscosities and density contrasts spanning the range considered typical for many calc-alkalic granitoids, dike ascent is a viable mechanism for the transport of large volumes of granitoid melt through the continental crust.
Nick Petford, Ross C. Kerr, John R. Lister   +2 more
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Granitoids and magmatic series: the contextualized study of granitoids.

2016
The relationship that many granitic rocks show with less differentiated mantle-derived magmas has been underestimated in the last decades and, that has led to the loss of a powerful scientific tool for the investigation of ancient geotectonic settings and, even for the evolution of the mantle-crust system.
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Structural features of some younger granitoids in central Sweden and implications for the tectonic subdivision of granitoids

Precambrian Research, 1991
Abstract Structural relationships are described along parts of the eastern margin of the 1.76-1.84 Ga old batholith, known as the Transscandinavian Igneous Belt (TIB). They demonstrate that the Svecofennian structures of the country rocks are highly dependent on the shape of the younger granitoids which themselves have margins folded in the same ...
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Granitoids of Sumatra and the Tin Islands

1988
The granitoid study by the Geological Research and Development Centre (GRDC) started in 1980. The investigation began in the Lampung area of the southernmost part of Sumatra and gradually moved northward to the Bengkulu, Jambi, and Tapanuli areas. In 1983 the investigation was carried out in collaboration with Dr. E.J. Cobbing and Dr. D.I.J.
null Wikarno, D. A. D. Suyatna, S. Sukardi   +2 more
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