In the northern Maluku Islands, three volcanoes are on alert level 2 / waspada, Gamalama, Ibu and Dukono. Tectonic earthquakes are recorded on the archipelago.
At Dukono, a white-gray plume 200 to 400 meters above the crater is observed on 23 November.
The PVMBG provides continuous tremor with a dominant amplitude at 2 mm.
These ash emissions are confirmed by VAAC Darwin.
As for the Ibu volcano, erupting since 2008, a thin gray plume rises between 200 and 800 meters above the summit, then pushed north and east. Strombolian activity is observed.
The PVMBG informs, for this 23 November, 69 earthquakes of eruption, 181 earthquakes of blast, harmonic tremor and a low frequency earthquake.
Sources: PVMBG, Magma Indonesia and VAAC Darwin
In the Philippines, the number of daily earthquakes continues to increase in recent days at Taal volcano: 73 on November 21, 82 on 22, and 100 on November 23.
Among the last recorded, we point the earthquake of 20:22 23,11, felt intensity 1 by the inhabitants of Brgy. Pira-piraso, Talisay, and Batangas.
The field measurements, made on November 21, in the eastern sector of the main crater lake, show an increase in temperature (32.8 ° C> 33.6 ° C), a drop in level (49 cm> 46 cm) and an inflation of the building.
The alert level remains at 1, suggesting that a dangerous rash is not imminent.
Source: Phivolcs
As part of a general volcanic agitation in the densely urbanized area of the Phlegrean Fields Caldera (Italy - Bay of Naples), the activity of the hydrothermal zone of Pisciarelli is increasing.
The seismic amplitude of Pisciarelli fumarolic tremor is an indicator of the fluid emission rate of the entire Solfatara - Pisciarelli hydrothermal system. The long-term analysis indicates a significant increase, by a factor of about 3, in the magnitude of quake events since May 2017. This increase corresponds to the trend of the geochemical and seismic parameters observed at Campi Flegrei, thus underlining that Pisciarelli is a key site monitor the ongoing volcanic troubles in this high-risk caldera.
Data analysis of three closely spaced seismic stations provided new clues to the source mechanism of the tremor. By analyzing the amplitude of fumarolic tremor, we could also identify an episode of enlargement of the emission zone near the main fumarole of Pisciarelli. A monitoring system based on fumarolic tremor analysis is proposed, which would provide real time information on the hydrothermal activity of Pisciarelli and therefore on the current troubles in the Campi Flegrei caldera.
Sources:
- INGV - Observatory of Vesuvius
- Agu - Insight into Campi Flegrei caldera unrest through seismic tremor measurements at Pisciarelli fumarolic field - Giudicepietro & al. 13,11,209