Please use this identifier to cite or link to this item: http://hdl.handle.net/2122/11766
Authors: Mollo, Silvio* 
Tuccimei, Paola* 
Galli, Gianfranco* 
Iezzi, Gianluca* 
Scarlato, Piergiorgio* 
Title: The imprint of thermally induced devolatilization phenomena on radon signal: implications for the geochemical survey in volcanic areas
Issue Date: 28-Jul-2017
Series/Report no.: /211 (2017)
DOI: 10.1093/gji/ggx314
URI: http://hdl.handle.net/2122/11766
Keywords: Magma chamber processes
Volcanic gases
Subject Classification04.08. Volcanology 
Abstract: Thermal gradients due to magma dynamics in active volcanic areas may affect the emanating power of the substrate and the background level of radon signal. This is particularly effective in subvolcanic substrates where intense hydrothermal alteration and/or weathering processes generally form hydrous minerals, such as zeolites able to store and release great amounts of H2O(up to ∼ 25 wt.%) at relative low temperatures. To better understand the role played by thermally induced devolatilization reactions on the radon signal, a new experimental setup has been developed for measuring in real time the radon emission from a zeolitized volcanic tuff. Progressive dehydration phenomena with increasing temperature produce radon emissions two orders of magnitude higher than those measured during rock deformation, microfracturing and failure. In this framework, mineral devolatilization reactions can contribute significantly to produce radon emissions spatially heterogeneous and non-stationary in time, resulting in a transient state dictated by temperature gradients and the carrier effects of subsurface gases. Results from these experiments can be extrapolated to the temporal and spatial scales of magmatic processes, where the ascent of small magma batches from depth causes volatile release due to dehydration phenomena that increase the radon signal from the degassing host rock material
Description: This article has been accepted for publication in Geophysical Journal Internationa ©: The Authors 2017. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. Uploaded in accordance with the publisher's self-archiving policy.
Appears in Collections:Papers Published / Papers in press

Files in This Item:
File Description SizeFormat 
ggx314.pdf3.18 MBAdobe PDFView/Open
Show full item record

Page view(s)

10
Last Week
0
Last month
0
checked on Jan 17, 2019

Download(s)

9
checked on Jan 17, 2019

Google ScholarTM

Check

Altmetric