Please use this identifier to cite or link to this item: http://hdl.handle.net/2122/12603
Authors: Giuffrida, Marisa* 
Viccaro, Marco* 
Ottolini, Luisa* 
Title: Ultrafast syn-eruptive degassing and ascent trigger high-energy basic eruptions
Issue Date: 2018
Series/Report no.: /80 (2018)
DOI: 10.1038/s41598-017-18580-8
URI: http://hdl.handle.net/2122/12603
Abstract: Lithium gradients in plagioclase are capable of recording extremely short-lived processes associated with gas loss from magmas prior to extrusion at the surface. We present SIMS profiles of the 7Li/30Si ion ratio in plagioclase crystals from products of the paroxysmal sequence that occurred in the period 2011-2013 at Mt. Etna (Italy) in an attempt to constrain the final ascent and degassing processes leading to these powerful eruptions involving basic magma. The observed Li concentrations reflect cycles of Li addition to the melt through gas flushing, and a syn-eruptive stage of magma degassing driven by decompression that finally produce significant Li depletion from the melt. Modeling the decreases in Li concentration in plagioclase by diffusion allowed determination of magma ascent timescales that are on the order of minutes or less. Knowledge of the storage depth beneath the volcano has led to the quantification of a mean magma ascent velocity of ~43 m/s for paroxysmal eruptions at Etna. The importance of these results relies on the application of methods, recently used exclusively for closed-system volcanoes producing violent eruptions, to open-conduit systems that have generally quiet eruptive periods of activity sometimes interrupted by sudden re-awakening and the production of anomalously energetic eruptions.
Appears in Collections:Papers Published / Papers in press

Files in This Item:
File Description SizeFormat 
Giuffrida M. et al. Scientific Reports_2018.pdfMain article1.51 MBAdobe PDFView/Open
Show full item record

Page view(s)

4
checked on May 27, 2019

Download(s)

2
checked on May 27, 2019

Google ScholarTM

Check

Altmetric