Alternative Magmatic Processes of Continental Growth in an Island Arc
نویسندگان
چکیده
منابع مشابه
Magmatic expressions of continental lithosphere removal
Gravitational lithosphere removal in continental interior has been inferred from various observations, including anomalous surface deflections and magmatism. We use numerical models and a simplified theoretical analysis to investigate how lithosphere removal can be recognized in the magmatic record. One style of removal is a Rayleigh-Taylor-type instability, where removal occurs through drippin...
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The production of small volume silicic rocks in areas of oceanic crust is understood with less certainty than the production of silicic rocks in a continental setting. While the anatexis of silicic continental crust produces rhyolites within a continent, it is unlikely to occur in Iceland, an island composed of basaltic oceanic crust. After analyzing rhyolitic samples I collected from multiple ...
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Tertiary andesitic basalts of the Sirjan area, Urmieh-Dokhtar Magmatic Arc, Iran, contain plagioclase phenocrysts enclosed in a matrix of amphibole, clinopyroxene and rare olivine crystals. Textural and compositional evidence suggests two significantly different types of plagioclase phenocrysts occur in the andesitic basalts. The most common type of plagioclase phenocrysts have zoning patterns ...
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ژورنال
عنوان ژورنال: Memoirs of the Faculty of Science, Kyūsyū University. Series D, Geology
سال: 1981
ISSN: 0023-6179
DOI: 10.5109/1546075