An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the
United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Google Analytics Dashboard for The stratigraphy of the Upper Cretaceous rocks north of the Arkansas River in eastern Colorado
The stratigraphy of the Upper Cretaceous rocks north of the Arkansas River in eastern Colorado