# Scenario-based forecast of the evolution of 75 years of unrest at Campi Flegrei caldera (Italy)

## TL;DR

Scientists model future volcanic activity at Campi Flegrei, suggesting magma is present but not yet large enough for a major eruption.

## Contribution

New thermal modeling and calculations reveal the current state of magma reservoirs beneath Campi Flegrei.

## Key findings

- A critically pressurized magma reservoir is present at ~4 km depth.
- The reservoir volume is smaller than the one that caused the 1538 eruption.
- It would take 2-3 decades for the reservoir to grow to a size capable of a major eruption.

## Abstract

Campi Flegrei last erupted in 1538 and periods of increased seismicity, gas emission and ground deformation occurred in the 50’s, 70’s 80’s and are ongoing since 2005. The eventual culmination of the unrest in an eruption, would directly impact on 2 million people living in the region, making it of critical concern for scientists, authorities and the public. Here, we use existing data, thermal modelling and calculations of the physical properties of magma, to provide plausible future scenarios, under the assumption that magma injection at 4-5 km depth is responsible for the unrest episodes recorded since 1950. Our calculations suggest that a critically pressurised reservoir containing potentially eruptible magma is present today at ~ 4 km depth. However, a major impediment to eruption is the reservoir volume, which would need 2-3 decades to grow to the size of the one that fed the last eruption of Campi Flegrei in 1538.

Thermal modelling and numerical calculations suggest that potentially eruptible magma is present at a depth of around 4 km beneath Campi Flegrei, but that the magma reservoir volume is currently smaller in comparison to the last eruption in 1538.