The alert level of the Santa Bárbara volcano, on Terceira Island, in the Azores, has been lowered from V3 (confirmation of system reactivation) to V2 (possible system reactivation), according to the Institute of Volcanology of the University of the Azores (IVAR).
“The Crisis Office decided to lower the volcanic alert level at the Santa Bárbara Volcano to V2”, reads a statement published on the website of IVAR and the Azores Seismovolcanic Information and Surveillance Center (CIVISA).
Since June 24, 2022, seismic activity in the Santa Bárbara volcano, on Terceira island, has been “above normal reference values”, with the most energetic event occurring on January 14, 2024, with a magnitude of 4.5 on the Richter scale.
On June 24, 2024, the alert level was raised from V2 to V3, due to seismic activity “frankly above normal levels” and “some signs of crustal deformation” [in rocky bodies], which indicated “the occurrence of a magmatic intrusion at depth”.
IVAR now reveals that the Crisis Office decided to lower the alert level, with a view to reducing seismic activity and crustal deformation.
“The Institute of Volcanology of the University of the Azores (IVAR), based on data obtained by the monitoring network of the Azores Seismovolcanic Information and Surveillance Center (CIVISA), informs that the seismovolcanic crisis that has been recorded on the island of Terceira since the day June 24, 2022 remains, with seismic activity and crustal deformation decreasing in the last two months to levels close to those observed until March of this year”, reads the statement.
IVAR warns, however, that “seismovolcanic activity on the perimeter of the Santa Bárbara Volcano, as a result of instability caused by a magmatic intrusion, remains clearly above reference levels, and the possibility of increasing again cannot be excluded, as already recorded in the recent past”.
“The danger related to the occurrence of earthquakes and slope movements therefore recommends that all preventive measures that have been published by civil protection authorities be maintained”, he says.
The volcanic alert level on the Serreta Submarine Ridge, also on the island of Terceira, which had been placed at V1 (state of instability) on September 9, 2024, was lowered to V0 (state of rest) “given that seismic activity in this geological structure returned to normal reference values”.
The scale of scientific alerts for characterizing the state of seismovolcanic activity in the Azores region, available on the IVAR and CIVISA pages, ranges from V0 to V6, where V0 means “resting state” and V6 “ongoing eruption”.