Amid the chaos of urban warfare, deciphering the truth behind each violent turn of events can be a difficult task, as facts become buried in piles of rubble or destroyed in plumes of smoke. However, a team of scientists from the University of Washington may have discovered a new technique for accurately determining the location, strength, and cause of a variety of explosion types, by studying vibrations picked up by seismographs. This could have a number of forensic applications, enabling military personnel and historians to correctly reconstruct key battlefield events.
Publishing their findings in the Bulletin of the Seismological Society of America, Ghassan Aleqabi and Michael Wysession studied the data detected by a seismometer at the Baghdad seismic observatory following a number of incidents during the Iraq war. In doing so, they found that differences in waveforms could be used to determine a number of key characteristics of each blast, providing a reliable historical account of these conflicts.
Seismometers measure vibrations caused by earthquakes, and while they have previously been used primarily for identifying the magnitude and epicenter of tremors, the researchers behind these latest findings insist that they could now also be used to record the effects of military operations in urban terrain (MOUTs).
For instance, when comparing the seismic vibrations produced by two car bombs that were detonated in June and December 2006, the researchers discovered that they were able to predict the location and weapon type of each. More specifically, their data suggested that while one of these bombs was detonated in an open setting, the other exploded in a narrow street, thus producing a more complex set of waveforms.
To check the accuracy of their predictions, the team cross-referenced their data with historical accounts of the attacks under observation.
They then turned their attention to a mortar attack on the U.S. Forward Operating Base Falcon, just outside the Iraqi capital, which occurred in October 2006. During this attack, heat from the exploding mortars caused stores of ammunition on the ground to blow up, generating what is known as an ammunition "cook-off." Analyzing the seismographs, the team was able to distinguish between a number of different types of explosions, which enabled them to reconstruct the entire series of events with remarkable accuracy.
In a statement, Wysession explained that “We could piece it all together, from the moment that the mortar hit. It was amazing to be able to take this bunch of squiggly lines [on the seismograms] and recreate this sequence of catastrophic destruction at the ammo depot.”
The study authors subsequently claim that the use of seismographic data could have a number of applications relating to MOUTs, as well as a range of non-military scenarios. For example, they cite an explosion at the Buncefield fuel depot in the U.K. in 2005, which was detected by seismometers in both England and The Netherlands. From these recordings, scientists were able to determine key information about the cause and timing of the blast.
