Monday, December 22, 2008

RoadTrip Update: Book Cliffs

Compared to the last time I drove by the Book Cliffs near Grand Junction, Colorado, a couple years ago (photo here), there was indeed a bit more snow when I drove by a couple days ago, although the snow was not deep.
The Book Cliffs are formed from a resistant sandstone in the Cretaceous Mesaverde Group - the two buff-colored cliffs at the top of the slopes above - which cap badlands formed on the Cretaceous Mancos Shale - the brownish to gray slope-forming unit below the capping cliffs. The Mancos Shale is fairly easy to recognize as you drive over it on I-70 in eastern Utah, because it is made of coaly beds and swelling clays, the latter of which cause the roadbed to become quite bumpy in places.
Above, a bit of detail in the Mancos Shale. Driving through the area from the San Rafael Swell into eastern Colorado always reminds me of the paintings of the artist Georgia O'Keeffe, who painted desert scenes and badlands, especially in New Mexico.

6 comments:

MJC Rocks said...

Beautiful! A geologist I knew who was part of the Uranium boom always referred to the Mancos as the d--ned Mancos Shale. But the formation has some spectacular moments! I hope you have a nice holiday!

Roads said...

That's wonderful, Silver Fox. I love the way that the snow laces the shale ridge.

Have you seen this book by Thomas Wiewandt and Maureen Wilks: The Southwest Inside Out? It's a cracker.

Maureen is now Manager of the Information Center at New Mexico Tech and a long time ago we did our undergraduate field mapping together in the Italian Dolomites.

ReBecca Foster said...

Glad to see you got some great pictures!! Hope your trip is going well!

Silver Fox said...

MJC, I kind of think of the Mancos that way, at least while driving across it, but the Book Cliffs are great!

Silver Fox said...

Roads, thanks for the info on the book; I tried to get it as a holiday present, but wasn't quick enough - so I guess I'll order it for myself!

Silver Fox said...

ReBecca, I did get some great photos from that pullout area, as you can see. The rest of the trip was good without hardly any weather problems, just a bit of a backup over Vail Pass where all the trucks take one lane and everyone else takes the other. I have been somewhat out of commenting range, but have been able to keep up to date on blog reading! Hope your holiday is going well!