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contained in the lower coal zone of the Raton Formation. The Raton Formation coals are also <br />targets for the gas industry and numerous CBM wells are active within the proposed permit area. <br />Overlying the Raton Formation are medium to coarse - grained to conglomeratic arkosic <br />sandstone beds intercalated and interbedded with greenish gray to maroon mudstone and <br />siltstones of the Poison Canyon Formation. The contact with the underlying Raton Formation is <br />indefinite and gradational. The Poison Canyon Formation caps the hills in the vicinity of the <br />New Elk Mine and can achieve thicknesses of several- hundred -feet. <br />Quaternary sediments consisting of alluvium, outwash and landslide material are found in the <br />bottom of the valley along the Purgatoire River and some tributaries. Quaternary alluvium <br />consists of an array of sediment size fractions ranging from clay to cobbles. The cobbles consist <br />of various rock types, including granite and were transported from western highlands and <br />deposited by the Purgatoire River and its tributaries. A description of the surface geology within <br />the New Elk Mine area is included under Geomorphology on Page 8 of the report by Water, <br />Waste and Land Ltd., reference 2 in Exhibit 8, Hydrology and Geology Information. <br />Within the environs of the proposed permit area, the surface material consists of Quaternary - <br />age alluvium ( "Qa" on Map 5) along the Purgatoire River and tributaries, Tertiary -age strata of <br />the Poison Canyon Formation ( "Tp" on Map 5) on the upper sides of the Purgatoire River Valley <br />and Cretaceous to Tertiary age sandstone, mudstone, siltstone and coal beds of the Raton <br />Formation on the lower slopes of the valley ( "TKr" on Map 5). The Vermejo is in the subsurface <br />and does not crop out within the confines of the proposed permit area. <br />Structurally, the Raton Basin is an asymmetric synclinal basin formed during the Laramide <br />Orogeny. The western flank of the basin dips steeply to the east and is displaced by transcurrent <br />and thrust faults. Strata dip becomes milder in the central and eastern areas of the basin and <br />within the permit area the dip ranges from 0 to 7 degrees and averages about 2.2 degrees east - <br />northeast. The axis of the northwest - southeast oriented La Veta Syncline occurs just east of the <br />proposed permit boundary (see Map 5, Regional Geology). On the eastern side of the basin the <br />strata dips mildly westward into the basin. <br />Fractures and cleats vary in orientation within the basin but in the New Elk proposed permit <br />area it appears to be oriented east -west to northeast - southwest. Faulting has been encountered in <br />the mines and within the Allen Mine the most significant fault encountered showed a vertical <br />displacement up to 30 feet (down - thrown on the south). The fault decreases in magnitude <br />eastward and forms a graben with a vertical throw of only 3 feet. Other minor faults were <br />encountered but rarely achieved full seam displacement and most were attributed to a <br />depositional mode of placement (i.e., paleoslumps). <br />The Raton basin was intruded by magma during the Miocene and Pliocene originating from <br />the Spanish Peaks igneous complex accompanied by extensive fracturing and emplacement of <br />igneous dikes, sills, plugs, laccoliths and stocks. The igneous dikes and sills are intermediate to <br />ultramafic in composition and, northeast of the permit area, these dikes trend east -west to <br />northeast - southwest. Dikes were rare in the underground workings but appear to become more <br />prolific north and east of the permit area. A thin igneous dike was traversed in the extreme <br />TR56 <br />2.04 -10 <br />Revised 1 /10 /11 <br />