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belt on the rim of the basin. These strata dip between 26 and 30 degrees to the southeast (into the <br />basin), and strike North 45° West. There are no mapped faults within the permit and adjacent <br />areas. Folding within the general area, however, has fractured the more brittle sandstone and <br />coal strata. The sandstones are resistant to erosion and form prominent ridges and cliffs at <br />outcrops. <br />Stream valleys in the vicinity of the Carbon Junction Mine are controlled by geologic structure. <br />The Animas River has cut a steep -sided valley perpendicular to bedding of the strata, and may be <br />related to a fracture or fault zone in Carbon Junction Canyon. <br />Stratigraphic units exposed in the area include (in ascending stratigraphic order): the Lewis <br />Shale, the Pictured Cliffs Sandstone, the Fruitland Formation and the Kirtland Shale. The <br />following coal seams in the Fruitland Formation underlie the Carbon Junction Mine: the Lewis <br />coal seam ( "C" seam), the Carbonero seam ( "B" seam) and the Shamrock seam ( "A" seam). <br />The Lewis Shale is the lowermost formation exposed in the vicinity. This formation consists of <br />between 1600 and 1800 feet of light to dark gray and black shales that contain interbeds of light <br />brown sandstone, sandy to silty limestones, calcareous concretions, and bentonite. This <br />formation is erosive and wide valleys have formed within this unit to the north. <br />The Pictured Cliffs Sandstone conformably overlies the Lewis Shale, is 200 feet thick, and <br />consists of two members. The lower member consists of 80 feet of interbedded shales and <br />sandstones. The Upper Pictured Cliffs Sandstone consists of 120 feet of massive sandstone with <br />some thin interbeds of shale and siltstone. The sandstone is white to light gray, well sorted <br />(uniform grain size), fine to medium grained, and contains silica and calcareous cement. This <br />sandstone is resistant to erosion and forms prominent ridges, cliffs, and steep sided stream <br />valleys (water gaps) in the area. (Fassett and Hind, 1971 and Shomaker, et. al., 1971.) <br />The Upper Pictured Cliffs Sandstone locally intertongues with the overlying Fruitland <br />Formation. The Fruitland Formation is coal- bearing. The Lewis or "C" coal seam is in the <br />Fruitland Formation. The Lewis coal seam is the lowest coal seam that was to be mined. <br />The Fruitland Formation is the coal bearing formation in the permit and adjacent areas. This <br />formation is composed of laterally discontinuous interbedded and lenticular sandstones, <br />siltstones, shales and coals. The formation is a terrestrial deltaic deposit and is gray to brown and <br />black with greenish shale and gray -green fine grained dense feldspathic sandstones in the upper <br />parts. <br />The Fruitland Formation contains three minable coal seams. In ascending stratigraphic order, the <br />seams are the Lewis or "C" seam, the Carbonero or "B" seam, and the Shamrock or "A" seam. <br />The Lewis seam is approximately 17 feet thick and consists of high volatile C bituminous coal. <br />The Carbonero or "B" seam is approximately 28 feet thick, contains a five -foot parting of shale <br />and bone, lies 105 feet above the Lewis seam, and is a high volatile C bituminous coal. The <br />Shamrock or " A" seam is located about 87 feet above the Carbonero seam, is about 21 feet <br />thick, and is classified as a high volatile C bituminous coal. The Shamrock seam is overlain by 0 <br />