Swarms of earthquakes have been affecting southern Italy since 2022, posing a threat to the population living above Campi Flegrei, a volcanic area experiencing slow vertical land movements. Researchers from Stanford University propose that managing water runoff or lowering groundwater levels could reduce fluid pressure within the geothermal reservoir and mitigate seismic activity.
The study, published in Science Advances on May 2, explores how pressure buildup from water and vapor in the reservoir under Campi Flegrei can lead to earthquakes when the caprock seals. This challenges previous theories attributing seismicity to magma rising to shallower depths. Instead, it suggests that changes in water recharge rates influence land deformation.
“To address the problem, we can manage surface runoff and water flow, or even reduce pressure by withdrawing fluids from wells,” stated Tiziana Vanorio, an associate professor at Stanford Doerr School of Sustainability.
The research involved analyzing patterns from recent periods of unrest characterized by land uplift and shaking. Grazia De Landro, co-author and researcher at the University of Naples Federico II, noted similarities in subsurface imaging over decades: “We have been looking at something that occurred decades apart… pointing not only to a cyclical pattern but also to a common underlying cause.”
Campi Flegrei has been monitored since significant unrest between 1982-1984 when Pozzuoli’s harbor became too shallow for docking due to land uplift. A magnitude-4 earthquake led to the evacuation of 40,000 residents.
“It’s been a challenge for the last three years. Many buildings have been damaged by continuous shaking,” said Vanorio, who was forced to evacuate as a child during earlier unrest.
Vanorio’s team used experiments simulating conditions in Campi Flegrei’s geothermal reservoir. They demonstrated how mineral fibers formed rapidly seal cracks in caprock under heat and pressure. The findings suggest that monitoring groundwater levels could prevent future seismic events.
Davide Geremia is a co-author of this study which hopes to inform local government officials about managing unrest proactively through better water management practices.
