Skip to content

CO2 gas content measured in the 2024 Svartsengi, Iceland eruptions used to elucidate magma storage conditions

Melissa Anne Pfeffer1 , Samuel Warren Scott2, Celine Lucie Mandon1, Michelle Maree Parks1, Andri Stefánsson2, Nicolas Levillayer2, Jón Bjarni Friðriksson1, Clive Oppenheimer3, Mike Burton4, Catherine Rachael Gallagher5

  • Affiliations: 1Service and Research Division, Icelandic Meteorological Office, Reykjavik, Iceland; 2Institute of Earth Sciences, University of Iceland, Reykjavik, Iceland; 3Department of Geography, University of Cambridge, Cambridge, UK; 4Department of Earth and Environmental Sciences, University of Manchester, Manchester, UK; 5Research and Development Division, HS Orka, Grindavik, Iceland

  • Presentation type: Poster

  • Presentation time: Friday 16:30 - 18:00, Room Poster Hall

  • Poster Board Number: 12

  • Programme No: 1.5.19

  • Theme 1 > Session 5

Abstract

The 2023-2024 eruptions within the Svartsengi volcanic system, Iceland are likely sourced by a series of sill-type magma bodies which reside within an extensive magma domain. These magma pockets are effectively modeled as a deflating Mogi source during each event to derive the optimal depth of the magma body that fails at the onset of each dike intrusion/eruption. CO2 is readily degassed from silicate melts at greater depths than other more soluble major volcanic gases. A diminishment of CO2 relative to H2O and SO2 measured in the gases released in the first stages of an eruption, in comparison with an expected initial composition, helps to reveal the pre-eruptive conditions of the magma. CO2 loss prior to eruption is a function of the storage depth of the individual magma pockets as CO2 solubility is strongly pressure dependent as well as the time available for segregation and loss. The time prior to an eruption allows the magma in the storage region to degas its insoluble CO2, while at the same time, fresher magma flowing in from a deeper source that contains close to the original CO2 content is mixing in. We present here a series of FTIR measurements of gases released early in these eruptions. In combination with the results of geodetic modeling, we use the CO2 content of the gasses to learn more about the contribution of outgassed CO2 to the measured deformation signal as well as the rate of CO2 loss in the magma storage region prior to each eruption.