Etna update, 21/04/2023
Mt Etna's resting phase also continued during the last two weeks. Seismic activity was slightly elevated and tremor increased somewhat.
During the past 14 days, clouds and fresh snow frequently hindered observation of the summit craters by webcams. During the cloud-free hours, the usual gas emissions appeared. These continued to be concentrated at Bocca Nuova, where there was strong and mostly pulse-like enhanced gas emission. At the Southeast Crater complex, gas and steam were emitted persistently from the area of the central crater or the upper section of the large breach, between the old and new Southeast Craters. Fractures or fumaroles also persistently emitted gas and white steam from the upper northern flank of New Southeast Crater. During the nights, light-intensive webcams also sometimes showed a glowing spot there.
At Northeast Crater and Voragine, on the other hand, I continued to observe hardly any gas emission.
The online seismograms of the ECNE station showed only sporadic, weak signals during the last 14 days. Many of the signals resembled explosion signals.
The tremor fluctuated along the boundary between low and medium levels and was recently subject to a slightly increasing trend [1].
Between 08.04. and 12.04. a series of weak earthquakes occurred in the area west of Monte Fontane (eastern flank), the strongest reaching a magnitude of 1.7. From 16.04. to 17.04. several weak quakes occurred at shallow depths in the area west of Piano Pernicana and east of Monte Nero (northeast flank), respectively. The strongest had a magnitude of 2.4. On 21.04. an earthquake with a magnitude of 4.4 was recorded southeast of Aci Castello (under the sea southeast of Etna). Several much weaker aftershocks followed [2].
1 - INGV-Sezione di Catania. 2023. Home. TREMORE VULCANICO. ECNE
2 - INGV. Osservatorio Etneo. Sorveglianza e Monitoraggio. DATABASE TERREMOTI. Localizzazioni di sala operativa. 2023.
