Monday, May 21, 2007 near Morrison, CO - After about five plus hours on the highway (with a lunch stop in Limon, CO) we finally arrived at our first geological stops on the west side of Denver. Our first stop was the spectacular I-70 roadcut south of Morrison, CO.
The cut is well known for its exposure of the Jurassic Morrison Formation and the Cretaceous Dakota Formation (which holds up the Hogback that this cut pierces). There are beautfully preserved sedimentary structures here, both Mesozoic and Quaternary (below).
Crossbedding in the Dakota sandstones (left) and mudcracks and trace fossils in the Qal (right).
But it’s not all fun and admiration… students get to break out their fieldbooks and Bruntons and start measuring. And yes, this is being graded.
Now what’s the trend and plunge on those slickensides, Carol?
