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-13- <br />The sedimentary rock formations within the permit and adjacent areas are <br />of Cretaceous Age. These are the Lewis Shale, the Pictured Cliffs <br />Sandstone, the Fruitland Formation and Kirtland Shale. <br />The Lewis Shale is the lowermost formation in the general area. This <br />formation consists of between 1,600 and 1,800 feet of light to dark gray <br />and black shales that contain interbeds of light brown sandstone, sandy <br />to silty limestones, calcareous concretions, and bentonite. This <br />formation is erosive and wide valleys have formed within this unit to the <br />north. <br />The Pictured Cliffs Sandstone conformably overlies the Lewis Shale, is <br />200 feet thick, and consists of two members. The lower member consists <br />of 80 feet of interbedded shales and sandstones. The Upper Pictured <br />Cliffs Sandstone consists of 120 feet of massive sandstone with some thin <br />interbeds of shale and siltstone. The sandstone is white to light gray, <br />well sorted (uniform grain size), fine to medium grained, silica and <br />calcic cemented. This sandstone is resistant to erosion and forms <br />prominent ridges, cliffs, and steep sided stream valleys (water gaps) in <br />the area. (Fassett and Hind, 1971 and Shomaker, et. al., 1971.) <br />The Upper Pictured Cliffs Sandstone is locally inter tongued with the <br />overlying Fruitland Formation. The intertongue of Fruitland Formation is <br />coal-bearing. The Lewis or "C" coal seam is located within this tongue <br />of the Fruitland Formation. The Lewis coal seam is the lowest coal seam <br />which will be mined. <br />The Fruitland Formation is the coal bearing formation in the permit and <br />adjacent areas. This formation is composed of discontinuous interbedded <br />and lenticular sandstones, siltstones, shales and coals. The formation <br />is a terrestrial deltaic deposit and is gray to brown and black with <br />greenish shale and gray-green fine grained dense feldspathic sandstones <br />in the upper parts. <br />The Fruitland Formation contains 3 minable coal seams, in ascending <br />order, these are the Lewis or "C" seam, the Carbonero or "B" seam, and <br />the Shamrock or "A" seam. The Lewis seam is approximately 17 feet thick <br />and consists of high volatile C bituminous coal. The Carbonero or "B" <br />seam is approximately 28 feet thick, contains a 5 foot parting of shale <br />and bone, lies 105 feet above the Lewis seam, and is a high volatile C <br />bituminous coal. The Shamrock or "A" seam is located about 87 feet above <br />the Carbonero seam, is about 21 feet thick. and is classified as a high <br />volatile C bituminous coal. The Shamrock seam is overlain by 0 to 120 <br />feet of overburden strata in the permit area. The entire overburden <br />section is in the Fruitland Formation. <br />The Kirtland Shale conformably overlies the Fruitland Formation. This <br />shale is divided into three main members, the upper and lower shales and <br />the middle Farmington Sandstone. The Farmington Sandstone member forms a <br />permanent ridge separating Carbon Junction Canyon and REA Canyon. The <br />lower shale member consists of gray to gray green shale and sandy <br />shales. The upper shale member consists of interbedded shales and <br />sandstones. <br />