AuScope seismometers used to detect unexploded bombs

In this recent collaboration, researchers from The ANU worked with members of the Royal Australian Air Force (RAAF), using seismic technology (that usually measures earthquakes) to locate unexploded bombs on weapons ranges. Video: RAAF

Have you heard of forensic seismology, the emerging field that studies human-made Earth vibrations, including nuclear explosions? Our AuSIS team from The ANU recently stepped into it in collaboration with the Royal Australian Air Force (RAAF). The group asked: could seismometers accurately locate unexploded bombs? This question yielded promising results through testing. The RAAF now has access to enhanced safety capability, as this video shows. And commercialisation may be next.

The approach

Professor Malcolm Sambridge (ANU) explains how the team, including Dr Michelle Salmon (ANU) and Daniel Stevens (RAAF), approached this experiment involving an array of AuScope seismometers:

'The two questions we set ourselves at the beginning of this experiment were: Could this type of vibration sensor detect a useful signal in these circumstances? If so, was it possible to make quantitative use of the data near real-time to practically locate the vibration source?

It took a combination of expertise in signal analysis, electrical engineering and seismology to answer these questions. As it turned out, both were positive.'

WATCH: Daniel Stevens explains how bombs generate seismic energy when they hit the ground. Video: RAAF

The results

This experiment has enabled RAAF staff to detect an exploded bomb within a 10-metre radius and an unexploded bomb within a 25-metre radius — both in near real-time instead of in days or weeks using a potentially hazardous manual process. This result is positive, paving the way for enhanced RAAF safety capability in the future.

WATCH: Woff Nicholas Stubbs-Race from the RAAF explains the positive impact of this project. Video: RAAF

An innovative process with exciting next steps

Here we capture project collaborators' reflections, including exciting next steps. RAAF collaborator Daniel Stevens is grateful for ANU's expertise and delights in the innovation process:

“Seismology is a dark art, it’s not something I wanted to do alone, and so I am very thankful to have The ANU there with us.

In the innovation process, you have to be willing to change fast and learn from your failures. I love the challenges. Every day is so dynamic, you don’t know what is coming the next day. You can set out a project timeline all you want, but that is going to change every single day and that’s what I love about it.”

Dr Michelle Salmon from The ANU explains the technical challenge at hand:

‘This project has challenged us (The ANU team) because most of the work that we normally do at the Research School of Earth Sciences is [to] look at distant [naturally occurring] earthquakes… and [here] we are looking at explosions and they have quite different signals.’

WATCH: Dr Michelle Salmon explains how AuScope seismometers can detect unexploded bombs. Video: RAAF

Professor Malcolm Sambridge agrees this was a (very welcome) challenge for the ANU team:

“We hope we can work together again, as this has been an interesting challenge based on 'out of the box’ thinking. It is just the type of thing that gets us excited.

It is a great example of how common approaches to earthquake detection and location can be repurposed in unusual ways for new benefit. This is particularly important when it comes to monitoring human-induced earth vibrations to ensure the Comprehensive Nuclear Test Ban Treaty is upheld globally, for example.”

 
 
 
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