Structural-stratigraphic framework and correlation of coal beds in the Tongue River and Sentinel Butte Members of the Fort Union Formation, Daglum 15-minute Quadrangle, Billings, Stark, and Slope counties, North Dakota

The Daglum quadrangle of southwestern North Dakota (see index map) is underlain by 11 lignite beds that exceed 5 ft in thickness within the Sentinel Butte and Tongue River Members of the Fort Union Formation.  Six of these bed crop out within the quadrangle.  This report illustrates the stratigraphic position, correlation, extent, and structural attitude of the lignite beds.