Researchers from Tel Aviv University identified weak seismic signals linked to vehicle movements inside Gaza before the attack
New research from Tel Aviv University suggests that seismic data could serve as an early warning system for potential terrorist activities.
Forensic seismology, typically used to monitor nuclear and conventional explosions, has revealed a groundbreaking application. In a study published last month in the peer-reviewed journal GeoScienceWorld, researchers from Tel Aviv University's Department of Geophysics identified weak ground motions associated with preparations for a terrorist attack. These motions were detected by analyzing seismic noise patterns generated by vehicular traffic.
On October 7, 2023, seismic stations in southern Israel recorded unusual vibrations caused by the movement of heavy vehicles -- tractors, bulldozers, and trucks -- inside Gaza.
The team analyzed data from three seismic stations, part of a nationwide network operated by the Israeli Geological Survey. These highly sensitive seismometers continuously monitor ground movements across Israel.
Israel's seismic network primarily aims to detect earthquakes and issue warnings about strong ground shaking. However, after the war, Dr. Asaf Inbal, who had been studying seismic sources often obscured by human-made noise, applied their expertise to decode seismic signals originating from Gaza as part of the war effort, Inbal explained to The Media Line.
Three stations -- located in Amatzia, Ktzi'ot, and Yatir, 30 to 50 kilometers from Gaza -- detected unusual seismic activity on the morning of October 7. This activity, recorded between 6 a.m. and 6:30 a.m., occurred before the onset of rocket fire. The researchers concluded with over 99.9% certainty that these signals originated within Gaza.
An unusual contrast aided in tracing these signals to vehicle movements in Gaza: On the Gaza side, approximately 6,000 people moved together within a short time frame, generating significant noise. Meanwhile, Simchat Torah kept most people at home on the Israeli side, creating a remarkably quiet background.
The noise originating from Gaza during this period was fundamentally different from typical patterns observed at the same
"The motions recorded near the seismometers were in the range of tens of nanometers per second, whereas the minimum ground motion detectable by humans is several millimeters per second," Inbal explained. "The noise originating from Gaza during this period was fundamentally different from typical patterns observed at the same stations on previous Saturdays."
The team reviewed three years of data recorded on Saturday mornings during the same time frame.
"We found no instance of a Saturday morning when correlated amplitudes were recorded at all three stations for over 10 minutes," Inbal said, noting that the stations are widely spaced and usually sensitive to local activity.
"For example, the distance between Ktzi'ot and Amatzia is about 80 kilometers. On previous Saturdays, there was no correlation between their data," he added. "On the morning of the attack, however, when local activity near the stations was minimal, we found unique, widespread seismic amplitudes that steadily increased as the attack approached. No known natural or human source on the Israeli side could have generated such signals."
The analysis indicated that vehicle movements originated along Salah al-Din Road, a significant route in Gaza stretching from Rafah in the south to Beit Lahia in the north. Moving at 25 to 50 kilometers per hour, these vehicles included bulldozers and trucks carrying operatives. Three minutes before the attack began, seismic signals were detected near Gaza's northern border at Beit Lahia, its southern border at Khan Yunis, and in central Gaza near Nuseirat.
We know the assault began almost simultaneously along the entire border
"We know the assault began almost simultaneously along the entire border," Inbal said. "These seismic observations provide further evidence of Hamas's extensive deployment, enabling the coordinated breach of the ground barrier."
Inbal clarified that while the Nova music festival generated some seismic noise, the analysis showed it was weaker and in different locations than the noise linked to Gaza.
A very solid conclusion from this study is that we can use anthropogenic noise recorded seismically to detect unusual activity around our borders
Due to security restrictions, Inbal could not confirm whether the IDF or intelligence agencies have implemented this seismic breakthrough. However, he emphasized its potential: "A very solid conclusion from this study is that we can use anthropogenic noise recorded seismically to detect unusual activity around our borders."