To the Phlegraean Fields increases both seismicity and ground uplift: according to the latest bulletin of the INGV Vesuvian Observatory, in the week from 3 to 9 November 2025, 165 earthquakesof maximum magnitude 2.5 (increasing compared to the 149 tremors of the previous week) while the average speed of ground lifting, linked to the bradyseismrose further to 25 ± 3 mm/montha stable value at 15 mm per month in the last 6 months.
From the point of view of the geochemical parameters, however, the already known warming trends of the hydrothermal system are confirmed, with an average value of ~94 °C at the Pisciarelli fumarole.
Despite the resumption of the phenomena, INGV did not detect elements that would suggest significant developments in the short term.
Seismic activity increases at Campi Flegrei: 165 tremors recorded
From 3 to 9 November 2025 the INGV located at the Campi Flegrei 165 earthquakes, with a magnitude between 0.0 and 2.5. Of these shocks, 61 were recorded during 3 seismic swarms occurred:
- The first swarm occurred on 04/11/2025 in the area of Pozzuoli-Ciglianowith 29 earthquakes of maximum magnitude 2.4.
- The second swarm recorded on 07/11/2025 in the area of Pozzuoli-Solfatarawith 6 earthquakes of maximum magnitude 2.2.
- The third swarm located on 09/11/2025 in the area of Pozzuoli-Pisciarelliwith 26 earthquakes of maximum magnitude 2.5.
As usual, the tremors had a reduced depth, typical of seismicity bradyseismic which is caused by the rising of the ground and not by the activation of faults. In particular, hypocenters were detected at depths ranging from 0.65 km to 3.82 km.
On the geochemical front, the parameters confirm the already known heating and pressurization trends of the hydrothermal system. In the area of Pisciarellithe temperature of the fumarole remains at an average value of 94°C. In the area of the crater of Solfatarahowever, the main fumarole (BG) confirms its increasing trend, with average values of ~166°C.
Bradyseism and soil uplift: the data
As for bradyseism, let’s go from 10 October 2025 INGV recorded an increase in ground lifting speedwith an average monthly lifting value that first reached 20±5 mm/month in the previous ones, and then settled at 25±3 mm/month.
This acceleration therefore marks an increase compared to the 15 ± 3 mm/month observed from early April to mid-October. Since the beginning of January 2025, the total lift recorded at the RITE GNSS station (Rione Terra) is approximately 18.5cm.
The latest bulletin on the Campi Flegrei in summary
In summary, the data from the latest weekly bulletin on the monitoring of the Campi Flegrei indicate:
- Seismicity: 165 earthquakes (Mdmax 2.5), up from 149 (Mdmax 2.1) the previous week.
- Swarms: three seismic swarms recorded on 4/11, 7/11 and 9/11, for a total of 61 tremors.
- Soil lifting: the average speed increases again to 25 ± 3 mm/month, up compared to 15 ± 3 mm/month in the period April-October 2025.
- Geochemistry: Stable parameters, with the Pisciarelli fumarole at 94 °C and the Solfatara at 166 °C.
