Please use this identifier to cite or link to this item:
Authors: Capasso, G.* 
Carapezza, M. L.* 
Federico, C.* 
Inguaggiato, S.* 
Rizzo, A.* 
Title: Geochemical monitoring of the 2002–2003 eruption at Stromboli volcano (Italy): precursory changes in the carbon and helium isotopic composition of fumarole gases and thermal waters
Issue Date: 2005
Series/Report no.: 68(2005)
DOI: 10.1007/s00445-005-0427-5
Keywords: Stromboli
Magma ascent
Dissolved gases
Subject Classification04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry 
04. Solid Earth::04.08. Volcanology::04.08.01. Gases 
04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring 
Abstract: Significant changes in the helium and carbon isotopic composition of shallow thermal waters vs. gas and a crater fumarolic gas have been recorded at Stromboli prior and during the 2002–2003 eruption. The 3He/4He ratios corrected for air contamination (Rc/Ra), and δ13C of fumarolic gases gradually increased from May to November 2002 before the eruption onset. These variations imply early degassing of a gas-rich magma at depth that likely fed both the intense Strombolian activity and small lava overflows recorded during that period. The lava effusion of late December 2002 was shortly preceded by a marked Rc/Ra decrease both in water and fumarolic gases. Comparison of He/CO2 and CH4/CO2 ratios in dissolved gas and with δ13CCO2 values rules out the Rc/Ra decrease due to an increasing input of radiogenic 4He. The Rc/Ra decrease is attributed to the He isotope fractionation during rapid magma ascent and degassing. A new uprising of 3He-rich magma probably occurred in January to February 2003, when Rc/Ra ratios displayed the highest values in dissolved gases ever measured before (4.56 Rc/Ra). The increase in He/CO2 and CH4/CO2 ratios and decrease in δ13C of dissolved CO2 was recorded after the 5 April 2003 explosive paroxysm, likely caused by enhanced gas-water interaction inducing CO2 dissolution. No anomalous Rc/Ra values were recorded in the same period, when usual Strombolian activity gradually resumed.
Appears in Collections:Manuscripts
Papers Published / Papers in press
Papers Published / Papers in press

Files in This Item:
File Description SizeFormat 
Capasso et al. Bull. Volcanol. 2005.pdfMain article470.77 kBAdobe PDFView/Open
Redirect Springer.htmlRedirect-Springer535 BHTMLView/Open
Show full item record

Page view(s)

Last Week
Last month
checked on Jun 20, 2018


checked on Jun 20, 2018

Google ScholarTM