What’s shaking?

Understanding underground explosions starts with better geologic models

August 1, 2021

Mandrel Pliers Test
The ground collapses several minutes after the MANDREL-Pliers test at the Nevada Test Site in August 1969. Scientists at Los Alamos use information from past nuclear tests to understand and identify seismic activity in the earth today.

By Elizabeth Miller

When the earth shakes anywhere in the world, scientists are keenly interested in what happened. Was it an earthquake? A chemical explosion? A collapsing mine? Or, was it a nuclear explosion?

At Los Alamos National Laboratory, we’re especially interested in the answer to the last question. Making sure the world is safe from nuclear proliferation means we need to monitor the globe for nefarious activity.

As you can imagine, a bad actor who wants to hide a nuclear test isn’t going to volunteer a lot of information regarding its whereabouts. That’s where nuclear explosion signatures come in.

A signature can come from seismic, acoustic or chemical signals — or all of the above. As a geologist at the lab, I’m most interested in understanding how rocks and subsurface features such as faults affect the seismic waves generated by the explosion. The speed at which those waves travel depends on the type of rock they move through.

Read the rest of the story as it appeared in the Santa Fe New Mexican.