The composition of gas emitted from a volcano producing basalt magma can vary during an eruption and according to the volcano-tectonic setting of the degassing vents. Post-eruptive filter-pack gas samples from the 2014–2015 Holuhraun crater in the Bárðarbunga rift zone have lower ratios of S over halogens (Cl and F) and elevated F/Cl (~ 50 times lower S/Cl and ~ 5 times higher F/Cl; mass ratios) compared with samples of the syn-eruptive gas plume. The compositional changes are readily explained by Rayleigh distillation with decreasing sulphur concentrations and increasing concentrations of halogens and F relative to Cl in the final gas phase. For Cl, the vapour-melt partition coefficient (DV/M) decreased from 13–85 to 2.2 during residual degassing, whereas that of F remained uniform at approximately 1.8. Distinctly different degassing behaviour is observed for Cl and F. High D for Cl may indicate an important influence of sulphur and water on Cl volatility in basaltic melt, whereas that of F remains unaffected. The primary gas of the Holuhraun magma had similar ratios of S over Cl and F as observed at the Kilauea rift zone which, together with lower S/halogens in the residual gas in both cases, suggests similar degassing mechanism. By inference, initial CO2 degassing is likely to have occurred subglacially close to the Bárðarbunga central volcano before and during the 2014–2015 eruption on the rift-related fissure swarm.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
This is the net price. Taxes to be calculated in checkout.
Aiuppa A (2009) Degassing of halogens from basaltic volcanism: insights from volcanic gas observations. Chem Geol 263:99–109
Aiuppa A, Federico C, Paonita A, Pecoraino G, Valenza M (2002) S, Cl and F degassing as an indicator of volcanic dynamics: the 2001 eruption of Mount Etna. Geophys Res Lett 29:1556. https://doi.org/10.1029/2002GL015032
Allard P, Burton M, Muré F (2005) Spectroscopic evidence for a lava fountain driven by previously accumulated magmatic gas. Nature 433:407–410
Alletti M, Baker DR, Scaillet B, Aiuppa A, Moretti R, Ottolini L (2009) Chlorine partitioning between a basaltic melt and H2O–CO2 fluids at Mount Etna. Chem Geol 263:37–50
Bali E, Hartley ME, Halldórsson SA, Guðfinsson GH, Jakobsson S (2018) Melt inclusion constraints on volatile systematics and degassing history of the 2014–2015 Holuhraun eruption, Iceland. Contrib Mineral Petrol 173:9
Burton M, Allard P, Muré F, Oppenheimer C (2003) FTIR remote sensing of fractional magma degassing at Mount Etna. In: Oppenheimer C, Pyle D, Barclay J (eds.), Volcanic degassing. Geological Society, London, Special Publication 2213: 281-293.
Carroll MR, Webster JD (1994) Solubilities of sulfur, noble gases, nitrogen, chlorine, and fluorine in magmas. In: Carroll MR, Holloway JR (eds.) Volatiles in magmas. Rev Mineral Geochem 30: 231–279.
Eaton JP, Richter DH, Krivoy HL (1987) Cycling magma between the summit reservoir and Kilauea Iki lava lake during the 1959 eruption of Kilauea volcano. US Geol Surv Prof Pap 1350:1307–1335
Edmonds M, Gerlach TM (2007) Vapor segregation and loss in basaltic melts. Geology 35:751–754
Edmonds M, Gerlach TM, Herd RA (2009) Halogen degassing during ascent and eruption of water-poor basaltic magma. Chem Geol 263:122–130
Edmonds M, Mather TA, Liu EJ (2018) A distinct metal fingerprint in arc volcanic emissions. Nat Geosci 11:790–794. https://doi.org/10.1038/s41561-018-0214-5
Fleet ME, Wu T-W (1993) Volatile transport of platinum-group elements in sulfide-chloride assemblages at 1000°C. Geochim Cosmochim Acta 57:3519–3531
Galeczka IM, Eiriksdottir ES, Pálsson F, Oelkers E, Lutz S, Benning LG et al (2017) Pollution from the 2014–15 Bárðarbunga eruption monitored by snow cores from the Vatnajökull glacier, Iceland. J Volcanol Geotherm Res 347:371–396
Gauthier P-J, Sigmarsson O, Gouhier M, Haddadi B, Moune S (2016) Elevated gas flux and trace metal degassing from the 2014-15 Holuhraun eruption (Bárðarbunga volcanic system, Iceland). J Geophys Res Solid Earth 121 https://doi.org/10.1002/2015JB012111.
Gerlach TM, Graeber EJ (1985) Volatile budget of Kilauea volcano. Nature 313:273–277
Gíslason SR, Stefánsdóttir G, Pfeffer MA, Barsotti S, Jóhannsson T, Galeczka I et al (2015) Environmental pressure from the 2014–15 eruption of Bárðarbunga volcano, Iceland. Geochem Persp Lett 1:84–93. https://doi.org/10.7185/geochemlet.1509
Greenland LP, Okamura AT, Stokes JB (1988) Gases from the 1983-84 east-rift eruption. US Geol Surv Pap 1463:145–153
Haddadi B, Sigmarsson O, Larsen G (2017) Magma storage beneath Grímsvötn volcano, Iceland, constrained by clinopyroxene-melt thermobarometry and volatiles in melt inclusions and groundmass glass. J Geophys Res Sol Earth 122. https://doi.org/10.1002/2017JB014067.
Halldórsson SA, Bali E, Hartley ME, Neave DA, Peate DW, Guðfinnsson GH et al (2018) Petrology and geochemistry of the 2014–2015 Holuhraun eruption, central Iceland: compositional and mineralogical characteristics, temporal variability and magma storage. Contrib Mineral Petrol 173:64. https://doi.org/10.1007/s00410-018-1487-9
Hudson TS, White RS, Greenfield T, Ágústsdóttir Th, Brisbourne A, Green RG (2017) Deep crustal melt plumbing of Bárðarbunga volcano, Iceland. Geophys Res Lett 44. doi:https://doi.org/10.1002/2017GL074749.
Ilyinskaya E, Schmidt A, Mather TA, Pope FD, Witham C, Baxter P et al (2017) Understanding the environmental impacts of large fissure eruptions: aerosol and gas emissions from the 2014–2015 Holuhraun eruption (Iceland). Earth Planet Sci Lett 472:309–322. https://doi.org/10.1016/j.epsl.2017.05.025
Mather TA, Witt MLI, Pyle DM, Quayle BM, Aiuppa A, Bagnato E et al (2012) Halogens and trace metal emissions from the on-going 2008 summit eruption of Kīlauea volcano, Hawai’i. Geochim Cosmochim Acta 83:292–323. https://doi.org/10.1016/j.gca.2011.11.029
Óladóttir B, Thordarson T, Larsen G, Sigmarsson O (2007) Did the Mýrdalsjökull ice-cap survive the Holocene thermal maximum? Evidence from sulfur contents in Katla tephra layers (Iceland) from the last ~8400 years. Ann Glaciol 45:183–185
Parfitt EA, Wilson L (1994) The 1983–86 Pu’ u ‘O’o eruption of Kilauea volcano, Hawaii: a study of dike geometry and eruption mechanisms for a long-lived eruption. J Volcanol Geotherm Res 59:179–205
Pétursson G, Pálsson PA Georgsson, G (1984) Um eituráhrif af völdum Skaftárelda (On the poisoning effect of the Skaftá Fires (Laki eruption)). In: Gunnlaugsson GÁ, Gudbergsson GM, Thorarinsson S, Rafnsson S, Einarsson, Th (eds) Skaftáreldar 1783-1784; ritgerðir og heimildir. Mál og menning, Reykjavik, pp.81-98.
Pfeffer MA, Bergsson B, Barsotti S, Stefánsdóttir G, Galle B, Arellano S, Conde V, Donovan A, Ilyinskaya E, Burton M, Aiuppa A, Whitty R, Simmons I, Arason Þ, Jónasdóttir E, Keller N, Yeo R, Arngrímsson H, Jóhannsson Þ, Butwin M, Askew R, Dumont S, von Löwis S, Ingvarsson Þ, la Spina A, Thomas H, Prata F, Grassa F, Giudice G, Stefánsson A, Marzano F, Montopoli M, Mereu L (2018) Ground-based measurements of the 2014–2015 Holuhraun volcanic cloud (Iceland). Geosciences 8:29. https://doi.org/10.3390/geosciences8010029
Reynolds HI, Gudmundsson MT, Högnadóttir T, Axelsson G (2019) Changes in geothermal activity at Bárdarbunga, Iceland, following the 2014–15 caldera collapse, investigated using geothermal system modelling. J Geophys Res Solid Earth. https://doi.org/10.1029/2018JB017290
Sharp ZD, Barnes JD, Fischer TP, Halick M (2010) An experimental determination of chlorine isotope fractionation in acid systems and applications to volcanic fumaroles. Geochim Cosmochim Acta 74:264–273. https://doi.org/10.1016/j.gca.2009.09.032
Sigmundsson F, Hooper A, Hreinsdóttir S, Vogfjord K, Ófeigsson B, Heimisson ER et al (2015) Segmented lateral dyke growth in a rifting event at Bárðarbunga volcanic system, Iceland. Nature 517:191–195. https://doi.org/10.1038/nature14111
Sparks RSJ (2003) Dynamics of magma degassing. In: Oppenheimer C, Pyle D, Barclay J (eds.), Volcanic degassing. Geological Society, London, Special Publication 2213: 5-22.
Stefánsson A, Stefánsson G, Keller NS, Barsotti S, Sigurdsson Á, Thorláksdóttir SB et al (2017) Major impact of volcanic gases on the chemical composition of precipitation in Iceland during the 2014–2015 Holuhraun eruption. J Geophys Res-Atmos 122:1971–1982. https://doi.org/10.1002/2015JD024093
Stelling J, Botcharnikov RE, Beermann O, Nowak M (2008) Solubility of H2O-and chlorine-bearing fluids in basaltic melt of Mount Etna at T= 1050–1250 C and P= 200 MPa. Chem Geol 256:102–110
Swanson DA, Fabbi BP (1973) Loss of volatiles during fountaining and flowage of basaltic lava at Kīlauea volcano, Hawaii. J Res US Geol Surv 1:649–658
Swanson DA, Duffield WA, Jackson DB, Peterson DW (1979) Chronological narrative of the 1969–71 Mauna Ulu eruption of Kilauea volcano, Hawaii. US Geol Surv Prof Pap 1056:1–55
Symonds RB, Rose WI, Bluth GJS, Gerlach TM (1994) Volcanic-gas studies: methods, results, and applications. In: Carroll MR, Holloway JR (eds) Volatiles in magmas. Rev Mineral Geochem 30: 1–66.
Thorarinsson S (1969) The Lakagigar eruption of 1783. Bull Volcanol 33:910–927
Thordarson T, Self S (2003) Atmospheric and environmental effects of the 1783–1784 Laki eruption: a review and reassessment. J Geophys Res-Atmos 108:4011. https://doi.org/10.1029/2001JD002042
Thordarson T, Self S, Oskarsson N, Hulsebosch T (1996) Sulfur, chlorine, and fluorine degassing and atmospheric loading by the 1783–1784 AD Laki (Skaftár Fires) eruption in Iceland. Bull Volcanol 58:205–225. https://doi.org/10.1007/s004450050136
Webster JD, Kinzler RJ, Mathez A (1999) Chloride and water solubility in basalt and andesite melts and implications for magmatic degassing. Geochim Cosmochim Acta 63:729–738
Zolotov MY, Matsui T (2002) Chemical models for volcanic gases on Venus. Lun Planet Sci XXXIII:1433
The field mission was financed by the French Laboratory of Excellence Program ‘ClerVolc’ and Institute of Earth Science, University of Iceland through Icelandic Governmental Civil Protection Grant. Sveinbjörn Steinþórsson and Ármann Höskuldsson are acknowledged for field assistance and photos taken during the gas sampling. Magnús T. Guðmundsson and Guðmundur H. Guðfinnsson are thanked for discussion on ice-cauldron formations and correcting the English. Comments from two anonymous reviewers were appreciated as well as the editorial handling by the three editors: Patrick Allard, Tobias Fischer and Jacopo Taddeucci. This is ClerVolc contribution number 411.
Editorial responsibility: P. Allard; Deputy Executive Editor: J. Tadeucci
About this article
Cite this article
Sigmarsson, O., Moune, S. & Gauthier, P. Fractional degassing of S, Cl and F from basalt magma in the Bárðarbunga rift zone, Iceland. Bull Volcanol 82, 54 (2020). https://doi.org/10.1007/s00445-020-01391-7
- Rayleigh distillation
- Volcanic gas
- Partition coefficients
- Holuhraun lava