[Rockhounds] Some boulders are precariously balanced. For seismologists, that's valuable

[Kreigh Tomaszewski]

They look like you could blow them over with a sneeze. Across the world,
thousands of "precariously balanced rocks
<https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020AV000182>" are
perched in strange positions, poised to topple. Once they would have been
mere geological curiosities. Now they are improving our understanding of
earthquake risk.

The fact that these delicately positioned boulders still stand provides
windows into deep history, long before modern-day seismometers could
measure the shaking ground. "The only witnesses that we can consult are
these precarious rocks – they're the witnesses of what once happened," says
geologist Dylan Rood of Imperial College London in the UK.

This, in turn, is allowing us to prepare for the future, by improving the
earthquake hazard maps which inform disaster plans, insurance premiums and
building codes. These wobbly, gravity-defying rocks are even helping
engineers stress-test nuclear power plants, radioactive waste repositories
and enormous dams.
https://www.bbc.com/future/article/20241115-the-benefits-of-precarious-boulders