"When you see those signals you know that's a mortar firing. You can begin to pick out what's going on," he added.
According to Wysession and his colleagues, earthquake monitors were initially installed in northern and northeastern Iraq to study the seismic properties of the Earth's crust in that area so that it would be possible to quantify the yield of nearby earthquakes or nuclear tests.
The situation changed when in October 2006 a mortar round hit the ammunition depot at US Forward Operating Base Falcon, south of Baghdad. The explosion was detected by one of the seismometers.
On that day, a group of unknown militants attacked the base with 82-mm mortars. After a shell hit the ammo supply depot it provoked explosions of various types of ammunition, including tank shells, regular explosive charges, mines, missiles etc.
The explosions lasted for nearly 24 hours. Most of them were recorded by the seismometer.
The scientists analyzed the seismic recordings and collected data. They figured out the seismic signatures which help locate an explosion, detect the type of an explosive or even predict further blasts and assess the possible damages.
The analysis took 10 years and has produced impressive results. Wysession and his colleagues have managed not only to identify seismic signatures for different types of explosives, but also to detect passing helicopters, distinguish between car bombs in open space and in narrow streets. The scientists have also managed to locate the firing position before a shell or mortar round hits the target.
According to the scientists, deploying earthquake monitors to large cities would tell security services a lot about terror attacks and help prevent them.
