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Point Lookout Sandstone. The Point Lookout Sandstone is a conspicuous, <br />• cliff-forming, white to buff sandstone, 300 to 400 feet thick. The <br />lower part of the member consists of thin-bedded sandstone which grades <br />downward into the Mancos Shale and upward into a massive sandstone. <br />Cross bedding is common, but is not conspicuous in the massive portion. <br />Menefee Formation. The Menefee Formation comprises a sequence of <br />interbedded shale and sandstone, approximately 350 feet thick. The <br />Formation contains several coal beds, two (2) of which are persistent <br />and potentially workable over wide areas. In general, the Menefee <br />Formation thins eastward from a maximum of about 350 feet to about 150 <br />feet. Lenses and beds of sandstone are irregularly interbedded with <br />shale. The proportion of sandstone to shale is highly variable. <br />In the Coal Gulch area, there are two (2) mineable coal seams generally <br />more than 3 feet thick. The upper, the "C" Coal Seam, is immediately <br />below the Cliff House Sandstone. In outcrops in Hay Gulch, this coal <br />• seam is fairly consistent and averages about 3 to 4 feet. <br />The next lower mineable bed, which is called the "A" Coal Seam, lies <br />below the "C" Coal Seam, and above the massive sandstone that caps the <br />Point Lookout Sandstone. It ranges in thickness from 5 to 6 feet. The <br />"A" Coal Seam has been mined more estensively in the Coal Gulch area <br />than the upper "C" Coal Seam and is probably the most important bed of <br />the area. <br />Cliff House Sandstone. The upper part of the Mesaverde Formation lying <br />above the Menefee Formation is referred to as the Cliff House Sandstone. <br />It consists of interbedded and interlensed sandstone and shale of <br />varying thicknesses. The general character of these upper beds is the <br />same as in the Menefee Formation, except that the sandstone beds are <br />more lenticular and the shale zones are essentially barren of coal. The <br />thickness of the Cliff House Sandstone varies greatly owing to the post <br />Mesaverde erosion, but is originally much in excess of 400 feet. <br /> <br />2.04-11 <br />