Seismicity of Deception Island volcano (Antarctica) from 2011-2022 surveys

Abstract

Since 1994, the Andalusian Institute of Geophysics of the University of Granada group has been monitoring the seismic activity of Deception Island volcano (South Shetland Islands, Antarctica) during summer surveys. In this review, we analyse long-period and volcanic-tectonic events, including tremor episodes, recorded from 2011–2012 to 2021–2022 surveys with a local network and a seismic array. The seismo-volcanic activity on Deception Island occurs very locally, mainly as a result of tectonic destabilization induced by volcanic activity along with regional stresses, as a consequence of rifting and subduction processes spanning the South Shetland Islands, Bransfield Strait and Antarctica Peninsula. During this period, two changes to the volcanic alert level due to different volcanic parameters can be highlighted. The first of them was caused by the 2014–2015 seismic swarm as a consequence of a great regional perturbation located to the north-east of Deception Island, which spread around to the entire volcano. The second one, in the 2019–2020 survey, was established as a result of a significant increase in deformation parameters as a prelude of the August 2020 massive earthquake swarm that occurred in the Bransfield Strait, near the Orca submarine volcano. Furthermore, in the previous 2018–2019 survey, a peak of seismic activity was also recorded.