POTD: Posted

POTD: Posted
November 15, 2016 Brian Truono
The basalt columns at Devils Postpile National Monument were formed approximately one hundred thousands years ago when lava pooled into the valley and slowly cooled into the unique hexagonal shapes. Likely during the last ice age, a glacier slid across the rock feature creating striations and glacial polish at the top of the cliff. Since the retreat of the glacier, the columns have been shedding from the main formation during the regular seasonal freezes and thaws. It’s fascinating to see how fire and ice, geology and meteorology work together to shape the earth’s surface. View Print Options

Comments (0)

Leave a reply

Your email address will not be published. Required fields are marked *

*

Newsletter sign up