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ceorogy <br />The applicant has supplied sufficient geologic information for the permit and adjacent areas within <br />the permit application. Geologic information contained within the permit application can be found <br />in Sections 2.04.5, 2.04.6; Table 4-1; Map 4-2; and Appendix 4-2 of the permit application. <br />The proposed Carbon Junction Mine permit area is located on the northern rim of the San Juan <br />structural basin in Southwest Colorado. The sedimentary strata in the permit area dip 26 to 30 <br />degrees to the southeast and strike North 45° West. There are no mapped faults within the permit <br />and adjacent areas. Folding within the general area, however, has produced fracturing within the <br />more brittle sandstone and coal strata. <br />The sandstones are resistant to erosion and form prominent ridges and cliffs at outcrops. Stream <br />valleys within the area of the proposed mine are controlled by the geology. The Animas River has <br />cut a steep sided valley perpendicular to bedding of the strata, and may be related to a fracture or <br />fault trend. Carbon Junction Canyon, which is tributary to the Animas River, has cut a channel which <br />pazallels the bedding of the strata in the less resistant shales, coals and siltstones of the lower <br />Fruitland Formation. <br />The sedimentary rock formations within the permit and adjacent areas are of Cretaceous Age. These <br />aze the Lewis Shale, the Pictured Cliffs Sandstone, the Fruitland Formation and Kirtland Shale. <br />The Lewis Shale is the lowermost formation in the general azea. This formation consists of between <br />1600 and 1800 feet of light to dark gray and black shales that contain interbeds of light brown <br />sandstone, sandy to silty limestones, calcareous concretions, and bentonite. This formation is erosive <br />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 consists <br />of two members. The lower member consists of 80 feet of interbedded shales and sandstones. The <br />Upper Pictured Cliffs Sandstone consists of 120 feet of massive sandstone with some thin interbeds <br />of shale and siltstone. The sandstone is white to light gray, well sorted (uniform grain size), fine to <br />medium grained, silica and calcic cemented. This sandstone is resistant to erosion and forms <br />prominent ridges, cliffs, and steep sided stream valleys (water gaps) in the area. (Fassett and Hind, <br />1971 and Shomaker, et. al., 1971.) <br />The Upper Pictured Cliffs Sandstone is locally intertongued with the overlying Fruitland Formation. <br />The intertongue of Fruitland Formation iscoal-bearing. The Lewis or "C" coal seam is located within <br />this tongue of the Fruitland Formation. The Lewis coal seam is the lowest coal seam which will be <br />mined. <br />The Fruitland Formation is the coal bearing formation in the permit and adjacent areas. This <br />formation is composed of discontinuous interbedded and lenticular sandstones, siltstones, shales and <br />coals. The formation is a terrestrial deltaic deposit and is gray to brown and black with greenish shale <br />and gray-green fine grained dense feldspathic sandstones in the upper parts. <br />a <br />