22 April 2016

Friday fold: Crumpled Dinwoody Formation, Sheep Mountain, Wyoming

Posted by Callan

Today for your folding pleasure, I give you two field GigaPans shot by Jeffrey Rollins, a two-time Rockies field course alumnus and Old Dominion University student working under my colleague Declan De Paor, assisted by NOVA student Bridget Gomez, during last summer’s extended GigaPan expedition at the Sheep Mountain Anticline, Wyoming.

This particular outcrop was found near the axis of the massive Laramide fold, and shows an extensively deformed section of Dinwoody Formation gypsum beds exposed along the creek bed just west of the anticlinal nose of Sheep Mountain. Because the deformation here was so well developed on the outcrop scale (as opposed to simply showing tilted beds that only show a fold at the scale of a map), they dubbed the site “fubarite” from the famous acronym. Check it out:

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Besides the fold, look for varying styles of strain in the different sedimentary layers, well-developed axial planar cleavage, and … dinosaurs! (Jeff and Bridget make these GigaPans more fun by hiding the dino ‘Easter eggs’ in them for students to find.)