Scientists discover keys to adjust earthquake risk in the Campi Furugrey Caldera, Italy

Earthquake swarms have been shaking Southern Italy with increased strength since 2022, threatening hundreds of thousands of people living above the volcanic region known as Campi Furgray.

While authorities are debating disaster response and evacuation protocols, researchers may have found ways to completely stop cyclical anxiety. By controlling water runoff or lowering the liquid pressure within the geothermal reservoir by lowering the groundwater level.

Through underground imaging and lab experiments, Stanford scientists have shown that pressure accumulation from water and steam in a reservoir under Campiful Gray leads to earthquakes by caprock, or lid, or lid, seal.

This study, published in Science Advances, shows that it is behind deformation and seismic activity in the early 1980s, and that it is behind deformation and seismic activity over the past 15 years, ultimately leading to the identification of underlying mechanisms.

The findings challenge the widely held theory that when magma or its gas is driven by a magma or its gas that rises to a shallower depth when it melts from a deep melting zone. They also reveal how the rate at which water gradually charges the reservoir affects the rate of deformation and change in land height.

“To address the problem, we can manage surface runoff and water flow, or reduce pressure by retracting liquids from the well,” said Tigiana Vanorio, associate professor of Earth and Planetary Science at Stanford Dore’s School of Sustainability.

The researchers analyzed repetitive patterns and common characteristics in imaging of underground structures, and analyzed earthquakes from two periods of Campi Flegrei’s latest anxiety.

Scientists say that this activity marks a steam-driven explosion triggered when liquid water rapidly steams and steams during an earthquake, and scientists are characterized by uplifts and burst-like shaking of the land, accompanied by rumbling sounds that are characteristic of the population. This study includes data from anxiety from 1982 to 1984 and 2011 to 2024.

“We have seen things happening decades apart, but there are deep similarities in imaging, pointing to not only the periodic patterns of phenomena, but also the common underlying causes.

“That’s where the idea began to look at rock physics in particular. Using rock physics is the only way to say quantitative things about underground imaging.”

The Campi Flegrei volcanic region features a geothermal reservoir covered under the town of Potzioli, west of Naples, west of Mount Vesuvius. The area has been continuously monitored as it has risen over six feet from the unrest of 1982-1984, with the Potzsori port becoming extremely shallow and the ships cannot be docked. A magnitude 4 earthquake and thousands of microcakes have since urged the evacuation of 40,000 people from Pozzuoli.

“The past three years have been a challenge. Many buildings have been damaged by continuous shaking, and some people do not have homes,” said Vanori, who grew up in Potzioli and was forced to be evacuated in the 1980s.

“This project is my goal not only as a geophysicist, but as a citizen, because it suggests that anxiety can pave the way for prevention rather than being monitored.”

Land that breathes

Campi flegrei is an eight-mile caldera and is a vast depression formed by a major eruption about 39,000 and 15,000 years ago, causing the collapse of the Earth’s surface.

Calderas experience uplifting and sinking even without eruptions. After the unrest of 1982-1984, the area sank about three feet. For settlement to occur, mass must be released from underground, which may contain magma, water, steam, and carbon dioxide.

Pozzuoli residents point out how the caldera emits smoke and moves down the ground, sometimes up and down meters in a short time.

Historically, volcanic areas’ uplifts have been widely accepted as being associated with magma-related replenishment processes. Although we assume that magma and/or its gases are the main factors in deformation and are responsible for earthquakes, research findings show that this is not necessarily the case.

Some researchers have begun to explore the relationship between precipitation and seismicity over the past decade, but this study reveals that it is not the rainfall itself, but rather the pressure caused by the slow and steady accumulation of water in enclosed reservoirs that lead to destruction.

“We know that annual fluctuations in rainfall have increased over the last 24 years, so what we need to monitor is to ensure groundwater buildup underground or direct channeling of water runoff,” Vanorio added.

Closed system

One notable feature of the Campi Flegrei is the fibrous nature of Caprock, located above a geothermal reservoir. Fibrous materials can be deformed without breaking quickly and are used in engineering for structural reinforcement. They can accumulate distortion. This could ultimately be released by a sudden eruption of superheated water, steam and volcanic ash.

Researchers looked at 24 years of rainfall patterns, groundwater flow direction, and Caprock Sealing processes to understand geothermal reservoir charging and its pressure accumulation. The Vanorio’s Rock Physics and Geomaterials Lab demonstrated how cracks in Caprock Seal are sealed through the interaction of rock minerals with hot water and steam.

To test the properties of Caprock, the research authors experimented with hydrothermal containers that function like a tool familiar to many Italians: Moka Pot, or Stovetop Espresso Maker.

They filled the bottom chamber with brine, then filled the top with crushed rocks into campi flegrei with volcanic ash and crushed rocks, then heated the vessel to the temperature seen in the geothermal reservoir. Within a day, mineral fibers were formed and cracks in the rock formations were rapidly sealed by cementation.

This creates a closed system where fluid pressure can accumulate until the surrounding rock is destroyed. Fragmentation from an earthquake causes a sudden drop in fluid pressure as liquid water flashes into vapor and escapes. “It produces explosive bursts and the vibrant sounds typical of the area,” Vanorio said.

The researchers applied multiple fields to reveal how Campi flegrei works as a closed system that includes underground tomography. This was performed using seismic records to construct underground images that could be analyzed like CT scans using seismic records.

“Imaging underground through geophysical methods is like an old-fashioned doorbell. It shows someone is ringing the door, but I don’t say who it is. Therefore, interpretation of tomographic images should be tested in the lab.

New model

The analysis of tomography and the location and extent of earthquakes contributed to the researcher’s theory that recurrent rumblings may not be driven by magma replenishment or gas emissions from the system. In both episodes of anxiety, the earthquake began within Caprock at a relatively shallow depth of about a mile.

“After visualising the temporal evolution of earthquakes, we can see very clear patterns. Earthquakes deepen over time,” said Tiannango, a postdoctoral scholar in Earth and Planetary Science, who combined seismic data from two episodes for visual interpretation.

Researchers say that if the magma or its gas rises from shallower depth to shallower depths, the opposite pattern will approach the deep melting region, and the aeroscake, which gradually becomes shallower over time, predicts the opposite pattern. Furthermore, the rise of magma without an eruption cannot explain the sinking following anxiety, Vanorio said.

A plausible explanation of subsidence is the observed discharge of water and steam after destruction from seismic activity that naturally releases pressure within the reservoir.

With a new model of Campi Flegrei’s inner workings, researchers hope to communicate to local Italian government officials the unsettling mechanism of the boiled system.

“I call it the perfect storm of geology. You have all the ingredients to have a storm: the burner of the system – the fuel for the geothermal reservoir, the lid,” Banorio said.

“We can’t work on burners, but we have the power to manage fuel. By restoring waterways, monitoring groundwater, and managing reservoir pressure, we can move geoscience to a more aggressive approach, detecting risks early and preventing anxiety before they can be deployed, like preventative healthcare.

Davide Geremia, a former postdoctoral scholar in Vanorio’s lab, is a co-author of the study.