Can earthquakes hide underground explosions?

New research from Los Alamos National Laboratory shows that earthquakes could obscure seismic signatures from nuclear testing in some scenarios.  

Read the paper

Why this matters: It is possible for a natural seismic event to mask human-caused explosions at a small range.  

• The research shows that the test case, which is a 1.7-ton buried explosion with the presence of background noise, had a 60% drop in detection rate with the addition of earthquake interference. 
• Earthquake swarms can further reduce the rate of detection. 
• Since there are relatively few explosion datasets that also have the presence of natural seismic signals, this paper is a step toward filling a research gap. 

How it works:  

• To compare seismic signals, the researchers used data from an International Monitoring System seismic array and from previous explosion experiments conducted at the Nevada National Security Sites.
• The team collected results in two separate one-month time periods in 2019, both of which included background noise.
• For an earthquake to hide an explosion, two conditions must be met. First, the explosion must be small enough that it is only detectable at a single array. Second, the explosion is contained so that traceable byproducts such as radionuclides do not leak out from the underground explosion site. 

Funding: National Nuclear Security Administration, Defense Nuclear Nonproliferation Research and Development