![A school building damaged from shelling in the city of Chernihiv, Ukraine](https://images.newscientist.com/wp-content/uploads/2023/08/30150454/SEI_169406630.jpg?width=1200)
A school building damaged from shelling in the city of Chernihiv, Ukraine
Dimitar Dilkoff/AFP via Getty Images
Existing seismometers in Ukraine – normally used to monitor nuclear weapons tests or detect earthquakes – have been repurposed to detect the times and locations of more than 1200 explosions in provinces near Kyiv. The explosive power registered by the seismometers also provides clues about the ammunition or weapons behind each blast.
“We’re automatically processing data and seeing explosions almost as they happen,” says Ben Dando at NORSAR, a seismic research foundation in Norway. “That has never been done in an active conflict in real-time before.”
Dando and his colleagues started out by looking for unusual explosions near Ukraine’s nuclear power plants in February 2022. They soon realised that they were picking up a wide variety of explosions as battles raged and Russian airstrikes targeted Ukrainian cities.
Using existing software and techniques, they quickly set up detection algorithms that could automatically provide alerts within 10 to 15 minutes of an explosion. Such algorithms can calculate the location and timing of each explosion based on when different seismic waves arrive at nearby seismic sensors.
The technique worked especially well within about 200 kilometres (124 miles) of the Malin seismic station northwest of Kyiv, which was originally established as part of an international network for monitoring nuclear explosions. That station has an array of 24 seismic sensors, each separated by up to 2 kilometres (1.2 miles), along with infrasound sensors that can detect sound waves typically inaudible to humans. But detection becomes more challenging in eastern Ukraine where fewer sensors exist.
The researchers previously used seismic data to identify an explosion that occurred in conjunction with the 6 June 2023 collapse of Ukraine’s Kakhovka dam, which was controlled by Russian military forces at the time.
Seismic monitoring holds the promise of tracking the number, timing and relative sizes of explosions, says Michael Pasyanos at the Lawrence Livermore National Laboratory in California. But he cautioned that the explosive yield estimates may not yet be precise enough to definitively identify a particular weapon behind each blast.
Seismic monitoring of conflicts would also be more difficult in the Middle East, Africa and South America, where there are relatively few seismic arrays, says Pasyanos. However, Dando suggested that portable seismic sensors might fill the gap. “You could rapidly deploy dense networks of portable seismic sensors and do a similar sort of analysis,” he says.
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