9 May 2017

Ripples in Foreknobs

Posted by Callan Bentley

The Foreknobs Formation is a Devonian unit in the Valley & Ridge province of the Mid-Atlantic Region. It was deposited in relatively shallow near-shore conditions during the Acadian Orogeny.

On a field trip to Corridor H, a new highway transecting the West Virginian Valley & Ridge province on Monday, I stopped to document a couple of beds showing very nice ripple marks.

These ones are symmetrical, and thus likely represent oscillating waves:

Here, two wave sets interfere with one another, amplifying and cancelling out each other’s bedforms:

Here’s a GigaPan of the scene:
Link 0.44 Gpx GigaPan by Callan Bentley

And here’s a 3D model: