This is the result obtained by Raffaele Rea, Simona Colombelli, Luca Elia and Aldo Zollo, of the Department of Physics, University of Naples, Federico II, in a paper recently published on Nature - Communication Earth & Environment.
https://www.nature.com/articles/s43247-024-01507-3
When an earthquake happens, seismic waves develop deep inside the Earth and propagate. Within seconds the waves reach the surface producing devastating effects on people buildings and infrastructure. Although it is not possible to predict earthquakes, it is possible to predict their impact on the land, and send an alert message to the site of interest in advance of the arrival of the potentially destructive seismic waves. This is how Seismic Early Warning systems work, on whose applications the research team has been working for several years . In collaboration with Reti Ferroviarie Italiane, they have developed the first prototype of a seismic early warning system for high-speed rail networks in Italy.
Here the authors demonstrated the potential and effectiveness of an Earthquake Early Warning system by applying it to seismic records of the devastating magnitude 7.8 earthquake in February 2023, which struck the region on the Turkey-Syria border. In the work, an advanced ground shaking prediction method was applied, based on the measurement of the first P waves, and capable of predicting, during an earthquake, the areas where ground motion will exceed a threshold limit of potential damage.
The performance of the system was evaluated through retrospective analysis of hundreds of accelerograms recorded near the earthquake source and acquired from the dense network operated by the AFAD agency of Turkey's Ministry of Interior. The first alert, issued about 10 seconds after the origin of the event, resulted in 95 % of sites correctly alerted, with warning times between 10 and 60 seconds within the potentially damaged area. The application showed that the zone of strong shaking predicted by P waves can be detected about 20 seconds after the origin of the rupture.
As time passes, in real-time, the system shows to accurately delineate the development of the seismic rupture, showing its bilateral propagation (in the NE-SW directions), as inferred from kinematic models of the rupture process determined in the aftermath by further offline investigations.
These important results show that P-wave-based Early Warning systems can provide timely and reliable alerts, reducing the risk of significant damage and improving the safety of people in seismic areas.