Powder River Basin Coal Field
In the Powder River Basin coal field – the most prolific in the world – coal is
mined from two major coal seams, the Anderson and Canyon coals. This coal occurs
in the Paleocene-age (65 to 55 million years ago) Tongue River Member of the
Fort Union Formation. The mineable subbituminous coal seams in the Fort Union
Formation are 60 to 80 feet thick, with a moisture content between 20 and 30
percent, and contain less than 6 percent ash and 0.5 percent sulfur. Powder
River coal also extends into the Eocene-age Wasatch Formation, and exploration
drilling has encountered coal seams greater than 200 feet thick.
Learn more about the PRB.
The Wyoming State Geological Survey is a major source of information on Wyoming’s coal and production efforts. Our coal geologists work to study, examine, and provide knowledge on coal geology and coal resources. We prepare and publish reports and maps, as well as develop educational products for the public.
Additional Information: Our latest Coal Map of Wyoming is available for free download. To purchase a hard copy map or associated datasets, please visit our Online Store.
- Coal Map of Wyoming (PDF)
- WSGS Coal Resources Summary Report
- WSGS Public Information Circular 44- Wyoming Coal
(307) 766-2286 Ext. 243