By Alessandro Rosi
Saturday 1 August 2026, 4:35 pm - Last updated: 5:15 pm
A 4.7 magnitude tremor, with landslides and rocks destroying cars. Fear returns to the Campi Flegrei. The toll is 21 injured (2 seriously) and hundreds displaced. We are talking about the most violent earthquake in 40 years, stronger than the 4.6 recorded on 30 June 2025. "In recent days, the uplift speed had increased slightly," warns seismologist Carlo Doglioni, vice president of the Accademia dei Lincei and professor of geodynamics at Sapienza.
Is there a progression underway?
"The sequence is ongoing, with events of gradually decreasing energy."
How long will it last?
"Barring further mainshocks, it should exhaust itself in a few days."
What origin do the earthquakes in that area have?
"The seismicity of the Campi Flegrei is volcano-tectonic in nature, that is, it is linked to the evolution of the volcano, and in this case it is generated by the upward thrust exerted by the magmatic melts intruding at shallow depth."
Is there a risk of a "big one"? Of a strong tremor?
"The limited size of the caldera prevents the generation of faults many km long, so there cannot be earthquakes of significantly higher magnitude than what we have recorded in recent years, perhaps a few tenths of a degree more at most."
Why?
"It must be borne in mind that the magnitude measured at the Campi Flegrei is different (duration magnitude) from that calculated in the rest of Italy or the world (moment magnitude): the duration magnitude gives values a few tenths of magnitude higher than the moment magnitude, which is the true energy released by the rupture. Earthquakes of magnitude between 4 and 4.9, in energy terms, are classified as 'light'. However, when the seismic source is very shallow (2-3 km), the ground shaking can be extremely significant."
And what does this entail?
"It must be verified where the rupture occurs, whether on land or in the Gulf of Pozzuoli: in the strictly epicentral area, very high ground accelerations can be detected, even close to the acceleration of gravity as happened yesterday. As long as the ground uplift continues, as has been happening since 2005, seismicity will continue. Currently the uplift is nonetheless slower than in the past (about 1 cm/month), but still incessant. In recent days, the uplift speed had increased slightly."
