Four Corners / Colorado Plateau Stratigraphy and Geology


Rock Units

Time Units


Structural Geology


Welcome to this Four Corners / Colorado Plateau Stratigraphy site. I've created it to fill in a gap in stratigraphic information that's easily available. There are good guidebooks, roadlogs, websites and scientific references. However, When I drive around the Four Corners, I get very confused. So I have created this website to tie together this disparate information. None of this website is original research, but I have tried to provide references for the origin of what you see.

Here are some generally useful starting places for people interested in the geology of this area:

The Utah Geological Survey has some fabulous resources for people wanting to understand the geology in their state.

Upper Triassic Lithostratigraphy, Depositional Systems, and Vertebrate Paleontology Across Southern Utah

Tectonosedimentary Relations of Pennsylvanian to Jurassic Strata on the Colorado Plateau, 2019, William R. Dickinson, Geological Society of America Special Paper 533, 184 pp.

A Traveler's Guide to the Geology of the Colorado Plateau, 2002, by Donald L. Baars

Navajo Country: A Geology and Natural History of the Four Corners Region, 1995, Donald L. Baars

Ancient Landscapes of Western North America: A Geologic History with Paleogeographic Maps by Blakey, Ronald C. and Wayne D. Ranney, 2008, Springer, pp. 228.

USGS MapViewer

This is an evolving project. It'll take some time to complete. I hope I finish it someday!