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• Mesaverde Formation <br />The Mesaverde Formation, which overlays the Mancos Shale, is divided <br />into four members which are, in ascending order: <br />• The Rollins Sandstone Member. <br />• The Lower Coal Member. <br />• The Upper Coai Member. <br />c The Barren Member. <br />Rollins Sandstone Member. The Rollins Sandstone Member is a <br />conspicuous, cliff-forming white to buff sandstone, 100 to 200 feet <br />thick. The lower part of the Member consists of thin-bedded sandstone <br />which grades downward into the Mancos Shale and upward into the massive <br />sandstone. Cross bedding is common, but is not conspicuous in the <br />massive portion. <br />• Lower Coal Member. The Lower Coal Member comprises in its lower part a <br />sequence of interbedded shale and sandstone, 50 to 180 feet thick, and <br />in its upper part, an irregular sandstone bed, 75 to 225 feet thick, the <br />top of which is taken as the top of the Lower Coal Member. The shalely <br />lower portion of this Member contains 2 to 4 workable coal beds, 2 of <br />which are very persistent and uniformly workable over wide areas. In <br />general, the shalely part of the Member thins eastward from a maximum of <br />180 feet to about 50 feet at the eastern Timit of the Paonia Coal Field. <br />Lenses and beds of sandstone are irregularly interbedded with shale. <br />The proportion of sandstone to shale is highly variable. The upper <br />sandstone of the Member is most conspicuous east of the town of Bowie, <br />where. it is readily recognized in outcrop. West of Bowie, it is more <br />lenticular and forms discontinuous cliffs. <br />The coal seams in the Lower Coal Member of the Mesaverde Formation are <br />different in both character and grouping in the western and eastern <br />parts of the Paonia Coal Field. The division between the 2 parts of the <br />• Field lies approximately along the Township line between Ranges 89 <br />2.04-13 <br />