Evidence for mantle metasomatism by hydrous silicic melts derived from subducted oceanic crust
نویسندگان
چکیده
منابع مشابه
Oceanic slab melting and mantle metasomatism.
Modern plate tectonic brings down oceanic crust along subduction zones where it either dehydrates or melts. Those hydrous fluids or melts migrate into the overlying mantle wedge trigerring its melting which produces arc magmas and thus additional continental crust. Nowadays, melting seems to be restricted to cases of young (< 50 Ma) subducted plates. Slab melts are silicic and strongly sodic (t...
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[1] We analyze short-period precursory energy to PP that can be observed in seismograms in the distance range from 95 to 105 to infer the behavior of subducted slabs beneath western Pacific subduction zones. PP is a P wave once reflected at the free surface between the source and receiver. Using high-resolution seismic array techniques, we analyze the incidence angle, timing, and azimuth of the...
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s CD. BODINIER, J.-L., MENZIES, M. A., SHIMIZU, N., FREY, F. A. & MCPHERSON, E. 2004. Silicate, hydrous and carbonate metasomatism at Lherz, France: contemporaneous derivatives of silicate melt–harzburgite reaction. Journal of Petrology, 45, 299–320. BONADIMAN, C., BECCALUVA, L., COLTORTI, M. & SIENA, F. 2005. Kimberlite-like Metasomatism and ‘garnet signature’ in spinel-peridotite xenoliths fr...
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ژورنال
عنوان ژورنال: Nature
سال: 2001
ISSN: 0028-0836,1476-4687
DOI: 10.1038/35065583