Friday Field Foto #63: Roadcut of Cretaceous strata near Morrison, Colorado
This week’s Friday Field Foto highlights a photo I took several years ago when I was working on my master’s in Colorado. A project for a clastic sedimentology class I was taking at the time required us to go visit a nearby roadcut outcrop, collect some data, and then synthesize our observations and interpretations.
This particular road cut is within the Cretaceous along the Front Range hogbacks (not too far from Denver).
Cretaceous Fox Hills Sandstone, Morrison, Colorado (© 2008 clasticdetritus.com)
The vertically-dipping yellowish rocks are sandstones and siltstones of the Fox Hills Sandstone (stratigraphic up is to the left). That is cut into by a very young alluvial surface with some gravel and reddish-brown sediment resting overlying the unconformity. And then there’s an anthropogenic unconformity on top of that with grayish/buff-colored fill from bulldozing activities (so we were told).
Check out this generalized cross section of the geology in this area.
Happy Friday!
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Clastic Detritus 
I ride my bike by this outcrop….I think I do anyway.
is this near the intersection of I-70 and colfax ave?
I occasionally see geology groups pulled over and looking at outcrops in this area…I really do feel lucky to live in an area with such striking geology.
Joe … I don’t remember exactly where it is, but, yes not far from I-70. I remember it being on a not too busy road … at least at that time it wasn’t very busy (~2002).