This is scientific American 60 second science.

I'm Julia Rosen.

Got a minute?

Rocks are pretty tough, but eventually, even the mightiest mountains crumble.

Geologists usually give the credit to water and ice, but when it comes

to smashing summits, a major player may be electricity in the form of lightning.

Scientists have found evidence for lightning's role in

mangling mountains in the magnetic signatures of rocks which go haywire

when blasted by bolts. I mean these magnetic anomalies are huge.

Susan Webb of the University of Vitwatersrand in South Africa.

And so we don't expect to see that not with ice fracturing rocks.

We would see that only with lightning fracturing rocks.

And the fact that there's so many tells you that this is a

really important mechanism for weathering rocks.

What presented her results on December 18th at the annual meeting of the American

Geophysical Union in San Francisco. As a test case, she studied the magnetic

signatures of rocks in the southern African country of Lesotho, a place with lots of

mountains and lots of lightning. But Webb says she's only

scratched the surface. And I think as we look more and more for this and it's very

easy to look for it if we do magnetic surveys in these areas, we will see it.

Then we'll be able to tell if this is a much more widespread phenomenon.

Thanks for the minute.

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