17 May 2016

Spheroidal weathering in Columbia River basalt

Posted by Callan Bentley

I’m in Idaho for the Rocky Mountain section meeting of the Geological Society of America.

Yesterday, I was delighted to tour around in eastern Washington’s Channeled Scablands with my colleague Bill Richards (North Idaho College). I took a lot of photos, but here are two to start – lovely examples of “onion skin” style weathering in fractured basalt, producing “kernstones” of increasingly spherical shape:

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This is a particularly well expressed example of a widespread and important phenomenon.