Friday, September 11, 2020

Hard Rock on Old Mountains



Hiked to Wolf Rock.

I wonder how many people and animals have fallen down into these deep crevices?

Not a good spot for a terrier; the dogs were left at home.

500 million years ago, this very hard quartize was a sandy sea bottom. It was compressed into extremely hard stone when the Appalachian mountains lifted up 200 million years ago.

We also have old lava flow here — Catoctin Mountain metabasalt, which is as hard as an Easter Island hammer stone.

The Appalachians are among the oldest mountains in the world, and were once as tall as the Rockies. This is the very hard stuff that has not eroded away.

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