Optical fiber to monitor earthquakes in Italy. What the Meglio project is and how it works

The fiber optic network present on the national territory could help earthquake swarm monitoringhelping to offer rapid and precise data to survey the territory.

These are the results of the project Bettera collaboration of Open Fiberthe National Metrology Research Institute (Inrim) and the National Institute of Geophysics and Volcanology (Engv), created to try to understand how optical fiber can be used as a sensor for detecting seismic waves.

The research data were published by the journal Natureamong the largest and most prestigious in the scientific community, after an analysis of the scientific community itself which they attested the solidity of the research method used. The publication certifies interest in the projectwhich could be crucial in areas more prone to earthquakes.

“The idea of ​​using the optical network to monitor and measure earthquakes came to us in 2018, after seeing a similar technology developed by Google Fiber during a telecommunications fair in San Diego” he explains Francesco Carpentieri Head of Transport Engineering at Open Fiber, the Italian company that creates the fiber network infrastructure in our country, usually dedicated to the transmission of data, images and telephone conversations.

“When we discovered that Google was working with Italian research institutes, we said to ourselves that we could do it too.” Unlike the Mountain View giant, which in the past started its experimentation using submarine cables, Open Fiber took advantage of its infrastructure on land.

What is Best and how does the project work

Better is an acronym. Stands for Measuring Earthquakes signals Gathered with Laser Interferometry on Optic Fibersmonitoring of earthquake signals collected from optical fiber signals. Seismicity monitoring in Italy is already a reality. It is made by a sensor network managed by Ingv.

The optical fiber is inserted as a support for these sensors. It is the fastest and most reliable electronic communication tool available at the moment. And this collaboration means that we can take a step forward in the sector of communication and monitoring of earth movements.

The fiber network created by Open Fiber extends from homes to the seabed, and turns out to be, the research explains, a fundamental tool for monitoring the territory, supporting and completing conventional sensors. Better confirmed the usefulness of this integration. Started in 2020, the project has created a seismic observatory that exploits a pair of Open Fiber optical fibers between Ascoli Piceno and Teramo as distributed sensors.

How the integration of fiber and sensors occurs

How does the integration work? The research explains that “a laser signal launched by the fibers, without interfering with normal data traffic, allows us to measure the microscopic elongations of the fibers caused by seismic vibrations”.

During the experiment – which lasted two years – several dozen seismic events were recorded, from the most disastrous such as the earthquake that occurred in Türkiye in 2023 to those more difficult to perceive, below magnitude level two. An analysis of the recordings, conducted by the INGV, confirmed the validity of the recorded data. And the potential of this technique as a permanent and widespread monitoring tool.

“What amazed INGV was precisely our ability to listen to micromagnitudes – said Carpentieri – the scientists were very surprised. What is news is that a network designed and created for telecommunications lends itself to this type of measurement. This is obviously a ready-made network and this would mean not having to invest further in new sensor networks, which are very expensive, for the same purpose, i.e. listening for possible earthquakes.”

The scientists of Nature – editors and therefore controllers of the data and results – confirmed the validity of the experiments. Which therefore could now become on a large scale, thanks to the involvement of the Civil Protection.

“While the INGV network is only present in places considered to be at the highest seismic risk, Open Fiber’s network covers a large part of the country and can therefore raise the alarm even if earthquakes occur in territories considered to be at low risk” says Carpentieri .

The researchers: “Fiber is an enabling element for the entire society”

“The publication in Nature confirms the interest and appreciation of the scientific community for Meglio, which is the first of a series of network sensing projects on which we are working and on which we are pioneers. Optical fiber is the enabling element of the digital evolution of our society, and Open Fiber, as a wholesale only operator, makes its network available to contribute to the development of an important area for our security such as seismic monitoring” he says Still Francesco Carpentierione of the main architects of the project.

While for Davide Calonicohead of the Quantum Metrology Division at Inrim, “the results of this study and their publication in a prestigious journal demonstrate how it is possible, also thanks to synergies between different communities, to achieve objectives with an impact not only for science but also for society, a mission that we consider fundamental”.

André Herrero, INGV’s first researcher, underlined that “the results emerging from this study open new frontiers in monitoring the seismicity and vulnerability of our cities, reaching our homes through the already existing fiber optic infrastructure. What makes this technology so promising are two key elements: its complementarity with current instrumentation and its sustainability thanks to the reuse of existing infrastructure. By combining sensorial capacity with data transport capacity, fiber optic monitoring can become a crucial player in prevention and early warning in the event of seismic events or tsunamis.”

v