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the area of the proposed mine are controlled by the geology. The Animas River has cut a steep sided valley perpendicular to bedding of the strata, and may be related to a fracture or fault trend. Cazbon Junction Canyon, which is tributary to the Animas River, has cut a channel which parallels the bedding of the strata in the less resistant shales, coals and siltstones of the lower Fruitland Formation. The sedimentary rock formations within the permit and adjacent areas are of Cretaceous Age. These aze the Lewis Shale, the Pictured Cliffs Sandstone, the Fruitland Formation and Kirtland Shale. The Lewis Shale is the lowermost formation in the general azea. This formation consists of between 1600 and 1800 feet of light to dazk gray and black shales that contain interbeds of light brown sandstone, sandy to silty limestones, calcazeous concretions, and bentonite. This formation is erosive and wide valleys have formed within this unit to the north. The Pictured Cliffs Sandstone conformably overlies the Lewis Shale, is 200 feet thick, and consists of two members. The lower member consists of 80 feet of interbedded shales and sandstones. The Upper Pictured Cliffs Sandstone consists of 120 feet of massive sandstone with some thin interbeds of shale and siltstone. The sandstone is white to light gray, well sorted (uniform grain size), fine to medium grained, silica and calcic cemented. This sandstone is resistant to erosion and forms prominent ridges, cliffs, and steep sided stream valleys (water gaps) in the azea. (Fassett and Hind, 1971 and Shomaker, et, al., 1971.) The Upper Pictured Cliffs Sandstone is locally intertongued with the overlying Frutland Formation. The intertongue of Fruitland Formation is coal-bearing. The Lewis or "C" coal seam is located within this tongue of the Fruitland Formation. The Lewis coal seam is the lowest coal seam that was to be mined. The Fruitland Formation is the coal bearing formation in the permit and adjacent areas. This formation is composed ofdiscontinuous interbedded and lenticulaz sandstones, sil[stones, shales and coats. The formation is a terrestrial deltaic deposit and is gray to brown and black with greenish shale and gray-green fine grained dense feldspathic sandstones in the upper parts. The Fmitland Formation contains three minable coal seams. 1n ascending order, these are the Lewis or "C" seam, the Cazbonero or "B" seam, and the Shamrock or "A" seam. The Lewis seam is approximately 17 feet thick and consists of high volatile C binmrinous coal. The Cazbonero or "B" seam is approximately 28 feet thick, contains afive-foot parting of shale and bone, lies 105 feet above the Lewis seam, and is a high volatile C bituminous coal. The Shamrock or "A" seam is located about 87 feet above the Cazbonero seam, is about 21 feet thick, and is classified as a high volatile C bituminous coal. The Shamrock seam is overlain by 0 to 120 feet of overburden strata in the permit area. The entire overburden section is in the Fmitland Formation. The Kirtland Shale conformably overlies the Fruitland Formation. This shale is divided into three main members: the upper and lower shales and the middle Farmington Sandstone. The Farmington Sandstone member forms a permanent ridge separating Cazbon Junction Canyon and REA Canyon. The lower shale member consists of gray to gray-green shale and sandy shales. The upper shale member consists of interbedded shales and sandstones. The Quaternary terrace deposits consist of Pleistocene aged gravels related to glaciation in the azea. Three gravel terace layers have been mapped in the azea and represent previous flood plains of the Animas River. These deposits vary between 1 and 100 feet thick and consist of boulders and cobbles in a silt clay matrix. Quaternary alluvial deposits are primarily located along the Animas River. Thin (less than three feet thick) isolated alluvial bodies are located in Carbon Junction Canyon.