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Geology- Rules 2.04.5 and 2.04.6 <br /> The applicant describes the geology of the permit and adjacent area in Section 2.04.6 of the PAP. <br /> Additional information is shown on Map 9, which details the geology of the permit area, as well <br /> as the coal outcrop line, and the strike and dip of the F, E and B Seams. Stratigraphic <br /> information is shown on Maps 10 through 23. <br /> The permit area lies on the southeast margin of the Piceance Basin and just south of Grand Mesa. <br /> The general geology of this area consists of gently(three to five degrees) north northeast dipping <br /> beds of sandstone, shale, and coal of upper Cretaceous and early Tertiary age. <br /> The geologic formations exposed in the North Fork Drainage Basin consist of Late Cretaceous to <br /> Early Tertiary Age sedimentary strata, Tertiary Age igneous intrusives, and Quaternary Age <br /> alluvial and colluvial deposits. The units are described below in ascending order. <br /> The Mancos Shale is the oldest stratum exposed in the region, and is of Late Cretaceous Age. <br /> This unit is composed of over 4,000 feet of gray marine shales and minor interbedded buff <br /> sandstones. This unit is highly erodible and unstable. Erosion and oversteepening of slopes in <br /> this formation produce the numerous rock falls and landslides observed in the lower North Fork <br /> Drainage Basin(Junge, 1978). <br /> The Mesaverde Formation is of Late Cretaceous Age and conformably overlies the Mancos <br /> Shale. This formation consists of approximately 2,300 feet of marine and terrestrial sedimentary <br /> rocks. The Mesaverde Formation is the coal bearing formation in the region and is divided into <br /> five main members; the Rollins Sandstone, the Lower Coal Bearing (Bowie) Member, the Upper <br /> Coal Bearing (Paonia) Member, the Barren(Undifferentiated) Member (Johnson, 1948), and the <br /> Ohio Creek Member. <br /> The Rollins Sandstone is a white to buff colored,well sorted, medium to fine grained sandstone, <br /> ranging from 150 feet to 300 feet thick. This sandstone is regionally extensive and resistant in <br /> outcrop and forms prominent cliffs. <br /> The Lower Coal Bearing (Bowie) Member consists of 260 to 350 feet of interbedded gray shales, <br /> thin to thick lenticular beds of buff colored, fine to medium grained sandstones, and coals. Three <br /> coal horizons exist in this member: the A (Old King) horizon, the B (Somerset) horizon, and the <br /> C (Bear) horizon. The A horizon is immediately above the Rollins Sandstone and is not <br /> currently mined at any operation in the vicinity. The B horizon contains two coal seams and <br /> occurs about 20 to 120 feet above the Rollins Sandstone and has been mined by MCC. This <br /> horizon has also been mined at the Elk Creek and Bowie #2 Mines. The C horizon contains one <br /> coal seam that occurs 50 to 100 feet above the B horizon. This horizon has been mined at the <br /> Elk Creek Mine and was mined at the Bear No. 1 and 2 Mines. The top of the member is usually <br /> capped by a massive buff colored sandstone up to 90 feet in thickness. This sandstone, however, <br /> appears not to be a single persistent bed, but is actually several thick lenticular sandstones <br /> occurring at progressively lower stratigraphic horizons from east to west. <br /> The Upper Coal Bearing (Paonia) Member consists of 200 to 500 feet of gray shales, <br /> interbedded, buff colored, lenticular sandstones, and coals. The top of this member is generally <br /> considered to be capped by a massive, cliff forming sandstone. Three coal horizons have been <br /> 16 <br />