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Like the Point Lookout Sandstone, the Cliff House Sandstone is reported to decrease in grain size in an eastward direction. Ten to fifteen miles East of the project area, the formation is composed of soft dark-gray mudstone and fine silty-shale with an occasional thin lense of fine ,grained sandstone in the lower part. The Cliff 1louse Sandstone has an average thickness of 350 feet throughout most of the project area. It shows a slight Eastward thinning, probably due to the increase in compactable fine sediments. ~ ' I Lewis Shale: The Lewis Shale conformably overlies the Cliff House Sandstone and consists of dark gray to black, nearly homogeneous clay shale with scattered concretions of dense argillaceous limestone and with a few thin seams of bentonite in the upper portion. The formation is reported to be about ],700 feet thick. The basal contact is very sharp with black flakey clay-shale sitting on gray mudstone or sand shale of the Cliff Hovse Sandstone. Structure: The geologic structure ~f the Hesperus area is characterized by gentle • Southward dips ranginy from 7° to 2° away from the structurally high La Plata Mountains to the North. It is probable that a small amount of faulting is present in the vicinity of the Town of Hesperus. A fault with a displacement of 33 feet has been reported in the old Hesperus mine in Section 14, Township 35 North, Ranye ]] West. Another fault, downthrown 30 feet to the East, has been reported in the Monarch Nine about. one mile t.ortheast of Hesperus. Results of exploration drilling conducted in the area have not revealed signi- ficant faulting. Surface Geolog Only the middle member of the Mesa Verde Croup is exposed on the property. The Mine is located on the South side of Hay Gulch with portals driven into the coal bearing Menefee Formation. 7'he Cliff Rouse Formation caps the higher ground on both sides of the gulch.