Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8911522 | Lithos | 2018 | 43 Pages |
Abstract
Santorini volcano sits ~145â¯km above the Aegean Wadati-Benioff zone, where the African plate subducts northward beneath Eurasia. There are only a few localities in the whole Aegean where basaltic lavas primitive enough to constrain mantle processes beneath the Aegean arc can be found; in this work we analyzed one such locality, a basalt lava from the southern part of Santorini. We apply a suite of petrological tools (PRIMACALC2 and ABS5) in sequence to estimate magma chamber conditions, primary magma composition, mantle melting conditions, and slab dehydration conditions. Back-calculation modeling based on major-element chemistry yields shallow magma chamber conditions of Pâ¯=â¯0.02â¯GPa, fO2â¯=â¯QFMâ¯+â¯2, and ~1â¯wt% H2O in the primary magma. The estimated major element composition of this primary magma then leads to estimated mantle melting conditions of 2.1â¯GPa, 1353â¯Â°C, and Fâ¯=â¯8%; whereas a more precise estimate derived from trace element modeling implies 1.7â¯GPa, 1323â¯Â°C, and Fâ¯=â¯18%. Furthermore, the trace element model implies a slab flux derived from 4.6â¯GPa (~150â¯km slab depth). The estimated slab depth, magma segregation conditions, and magma chamber depth are all consistent with seismic observations, supporting slab dehydration in the seismically imaged steep slab interval and flux melting in a relatively hot mantle wedge.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Geochemistry and Petrology
Authors
Ioannis Baziotis, Jun-Ichi Kimura, Avgoustos Pantazidis, Stephan Klemme, Jasper Berndt, Paul D. Asimow,