Some problems in the mantle origin hypothesis of calc-alkaline magmas
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منابع مشابه
Ultra-calcic Magmas Generated from Ca- depleted Mantle: an Experimental Study on the Origin of Ankaramites
Ultra-calcic ankaramitic magmas or melt inclusions are ubiquitous in arc, ocean-island and mid-ocean ridge settings. They are primitive in character (XMg 4 0 65) and have high CaO contents (414 wt %) and CaO/Al2O3 (41 1). Experiments on an ankaramite from Epi, Vanuatu arc, demonstrate that its liquidus surface has only clinopyroxene at pressures of 15 and 20 kbar, with XCO2 in the volatile comp...
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Hornblende occurs in some andesitic and basaltic rocks of calc-alkaline affini1y, where it is commonly associated with olivine. The texture, eruption history, and composition are interpreted to indicate that hornblende commonly forms as a product of reaction between olivine and basaltic and andesitic liquids. The natural hornblendes probably formed within the crust at temperatures between 960o ...
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predicted effects, but more complete sample suites yielding detailed Modeling of equilibrium reactive melt transport in the mantle, temporal–compositional variations of clearly cogenetic lavas are including the effects of mineralogic reactions and changes in porosity needed to test the petrogenetic significance of reactive melt transport in the solid matrix, provides a series of robust predicti...
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clicking here. colleagues, clients, or customers by , you can order high-quality copies for your If you wish to distribute this article to others here. following the guidelines can be obtained by Permission to republish or repurpose articles or portions of articles ): April 5, 2012 www.sciencemag.org (this information is current as of The following resources related to this article are availa...
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Liquidus phase relationships have been determined for a high-MgO basalt (STV301: MgO 12.5 wt%, Ni 250 ppm, Cr 728 ppm) from Black Point, St Vincent (Lesser Antilles arc). Piston-cylinder experiments were conducted between 7.5 and 20 kbar under both hydrous and oxidizing conditions. AuPd capsules were used as containers. Compositions of supraliquidus glasses and mass-balance calculations show th...
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ژورنال
عنوان ژورنال: The Journal of the Geological Society of Japan
سال: 1970
ISSN: 0016-7630,1349-9963
DOI: 10.5575/geosoc.76.529