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The Geophysical significance of calc‐alkaline andesites in New Zealand
New Zealand Journal of Geology and Geophysics, 1969Abstract Andesite volcanoes of the North Island of New Zealand are divided on the basis of their potash contents into two groups; a low potash group which includes the Northland, Coromandel, and Taupo Volcanic Zone andesites, and a high potash group which contains the volcanoes of western Taranaki. There are no significant differences
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The multistage crystallization of zircon in calc‑alkaline
2016CL imaging and U–Th–Pb data for a population of zircons from two of the Évora Massif granitoids (Ossa-Morena Zone, SW Iberia) show that both calcalkaline granitoids have zircon populations dominated by grains with cores and rims either showing or not showing differences in Th/U ratio, and having ages in the range ca.
Pereira, M. Francisco +7 more
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Amphibole stability in H2O-undersaturated calc-alkaline melts
Earth and Planetary Science Letters, 1972Abstract The upper stability limit of amphibole in silicate melts has previously been shown to increase in temperature when the mole fraction of H 2 O in the fluid phase in equilibrium with the melt was decreased from 1.0 to 0.5. New experiments on amphibole stability in melts of andesite composition show that the amphibole stability limit also ...
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Magma mingling, zoning and emplacement in calc-alkaline granitoid plutons
Tectonophysics, 1989The study of some Carboniferous orogenic granitoid plutons from northern Sardinia reveals the close relationship between their composition and the abundance of the enclosed mafic magmatic inclusions. The latter represent blobs of mingled basaltic magma. Most of the plutons are normally zoned with their felsic character increasing towards the core. This
M.J Zorpi +3 more
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Crystal clots, amphibole fractionation and the evolution of calc-alkaline magmas
Contributions to Mineralogy and Petrology, 1979Petrographic and microprobe investigations of calc-alkaline (CA) rocks from the High Cascade Range (i.e., Mt. St. Helens, Mt. Jefferson, Crater Lake and Mt. Shasta) of western North America show that crystal clots represent primary igneous phase assemblages and are not products of amphibole reactions with melt.
Garcia, Michael O., Jacobson, Sara S.
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Calc-alkaline plutonism in the intra-oceanic Aleutian arc, Alaska
1990Some of the best developed calc-alkaline plutons in an oceanic island arc are found in the Aleutian arc, Alaska. These Tertiary plutons are similar in many ways to continental granodioritic I-type plutons, but are smaller and have isotopic ratios and Rb contents that reflect their oceanic setting.
S. Mahlburg Kay +3 more
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Biotites in calc-alkaline intrusive rocks
Mineralogical Magazine, 1973M. J. Neilson, S. J. Haynes
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Distribution of elements in igneous rocks of the normal calc-alkaline sequence
Scottish Journal of Geology, 1969Synopsis Compilations of published data on the abundance of elements in normal plutonic igneous rocks are given in 14 graphs, each of which depicts the data for a particular group of elements.
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Tracing the Cambro-Ordovician ferrosilicic to calc-alkaline magmatic
2017U–Pb geochronological study of zircons from nodular granites and Qtz-diorites comprising part of Variscan high- grade metamorphic complexes in Gredos massif (Spanish Central System batholith) points out the significant presence of Cambro-Ordovician protoliths among the Variscan migmatitic rocks that host the Late Carboniferous intrusive granitoids ...
Diaz-Alvarado, Juan +4 more
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Amphibole fractionation in calc-alkaline magma genesis
American Journal of Science, 1976R. G. Cawthorn, M. J. O'Hara
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