کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5785087 1639931 2017 106 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Three years (2011-2013) of eruptive activity at Mt. Etna: Working modes and timescales of the modern volcano plumbing system from micro-analytical studies of crystals
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی
پیش نمایش صفحه اول مقاله
Three years (2011-2013) of eruptive activity at Mt. Etna: Working modes and timescales of the modern volcano plumbing system from micro-analytical studies of crystals
چکیده انگلیسی
Chemical zoning of olivine crystals highlights processes of multi-step magma transfer and residence at different levels of the plumbing system. The upward migration of magmas occurred primarily through multiple episodes of injection and mixing between five compositionally distinct magmatic environments (Mi), whose P-T-ƒO2 characteristics and concentrations in dissolved volatiles were constrained by thermodynamic modeling on the basis of the forsterite contents found at the olivine cores. From a deepest reservoir, located at depth of ~ 600 MPa, the most primitive magma M00 (Fo84) moved along dominant pathways, intercepting the M0 (Fo80-82) at ~ 390 MPa and/or M1a (Fo78; 250 MPa), M1b (Fo75; ~ 140 MPa) and finally the shallow M2 (Fo70-73; ~ 40 MPa) storage zones. For some eruptive episodes, olivine zoning highlights a preferential route of transfer, connecting the M00 and M2 storage zones that facilitated the fast migration of primitive magma at shallow depth. Fe-Mg diffusion modeling on olivine normal and reverse zoning defines the timescales of magma transfer and storage across these magmatic environments, which vary from ~ 1 to 18 months, whereas intrusion and mixing by more basic magma into the shallowest reservoir occurred always within 5 months before the eruption. Relevance of this study mainly relies on the quantification of volcanic processes at depth that may have considerable consequences in development of unusual, high-energy eruptions at basaltic volcanoes, generally acknowledged for their weak to mild explosive activity.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Earth-Science Reviews - Volume 171, August 2017, Pages 289-322
نویسندگان
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