@misc{10481/71241,
year = {2021},
month = {8},
url = {http://hdl.handle.net/10481/71241},
abstract = {Deception Island (South Shetland Islands, Antarctica) is an active volcano characterized by a moderate level of
seismic activity, dominated by long-period seismicity related to hydrothermal processes in a shallow aquifer.
Nevertheless, in the last few decades the volcano has undergone at least three episodes of seismic unrest, in
1992, 1999, and 2015. During these episodes, the pattern of seismicity changed, and swarms of volcanotectonic
earthquakes with hundreds of events in time spans of a few months were detected. These episodes
are interpreted as consequences of magmatic intrusions. However, the seismic series display significant differences
that lead us to think that the processes initiating the series are not exactly the same in all cases. The
1999 series comprisedmostly small-magnitude earthquakes, produced regularly during 1.5 months, and located
at shallow depths (<4 km) within the caldera, mostly along a WSW-ENE trend that parallels the Bransfield rift.
No precursory seismic activity was reported, and a few months after the series onset the seismicity was back to
normal levels. The 2015 series included earthquakes with largermagnitudes, occurring during 5 months in temporal
clusters separated by aseismic periods. They were located at deeper levels (<10 km) with epicenters distributed
all around Deception Island, at distances up to 30 km. Additionally, distal (~35 km) VT seismicity was
reported SE of Livingston Island months before the 2015 series onset, and the seismicity at Deception Island
remained anomalously high during a few years. Taking into account the limited data available for the 1992
unrest, we conclude that the 1992 and 1999 series were produced by shallow, short-lived, small-volume
(~4·104m3) intrusions that affected the shallowmost part of the volcanic edifice. On the contrary, the 2015 series
was consequence of a deep, long-lasting intrusion that involved a larger volume of ~5·106 m3 (in the range of a
VEI 2 eruption) and modified the stress field of the whole volcanic edifice.},
organization = {Youth Employment Program of the Junta de Andalucia, Spain	2018-6032},
organization = {project BRAVOSEIS - Spanish Ministry of Science (MINECO)	CTM2016-77315-R},
organization = {Univeristy of Granada/CBUA},
publisher = {Elsevier},
keywords = {Volcano-tectonic earthquakes},
keywords = {Seismic swarms},
keywords = {Magma intrusions},
keywords = {Failed eruptions},
keywords = {Volcano seismicity},
keywords = {Deception Island volcano},
keywords = {Antarctica},
title = {On the origin of recent seismic unrest episodes at Deception Island volcano, Antarctica},
doi = {10.1016/j.jvolgeores.2021.107376},
author = {Moreno Vacas, Alejandro and Almendros González, Francisco Javier},
}