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DocuSign Envelope ID:6BC32598-B737-464E-898A-81 F1 F7131339133 <br /> Frontier Sandstone Member—The Frontier Sandstone Member of the Mancos Shale contains an <br /> upper unit of interbedded gray and tan sandstone and gray shale and a lower unit of brownish <br /> gray shale with thin bentonite beds. Thickness of the combined units is approximately 310 ft in <br /> thickness. The top of the Frontier Sandstone Member lies about 400 ft above the base of the <br /> Mancos Shale. <br /> Dakota Sandstone—The Dakota Sandstone in the sub-basin has upper and lower parts consisting <br /> of light gray quartzite sandstone with dark chert pebbles, separated by a middle part consisting <br /> of dark gray fissile shale. Combined thickness averages approximately 100 ft. <br /> Entrada Sandstone—The Jurassic Entrada Sandstone is a gray, buff, and to a lesser extent pink, <br /> predominantly cross-bedded, medium to thick bedded, fine to medium grained sandstone. <br /> Thickness has been reported at up to 45 ft in western Moffat County. <br /> Shinarump Sandstone — The Triassic Shinarump Formation in northwestern Colorado and <br /> northeastern Utah has been described as coarse-grained conglomeratic deposit at the base of the <br /> Chinle Formation by Dubiel, 1992. <br /> Weber Sandstone — Johnson, 2003 describes the Weber Sandstone near Rangely, Colorado as <br /> yellowish-white,fine-grained,subarkose to quartzarenite.The Weber Sandstone is approximately <br /> 1,100 ft thick near Rangely and thins to the east to the to 370 ft north of Meeker, Colorado(Gibbs, <br /> 1982). <br /> Structure <br /> The area around the mine is dominated by the Axial Basin Uplift, an anticline or arch, which is a <br /> southeastward extension of the larger Uinta Mountain Arch. The Axial Basin Anticline is an <br /> asymmetrical fold,the axis of which trends north 60'west, with strata dipping(inclining) steeper <br /> on the south side of the axis than on the north. The south flank of the anticline has several <br /> secondary folds trending subparallel and at approximate right angles to the main anticlinal axis. <br /> In general, the rocks of the broad anticline have not been stressed sufficiently to cause them to <br /> break severely, but a few discontinuous normal faults trending primarily parallel to the anticlinal <br /> axis are found in the area. <br /> The structure of the northeast flank of the Piceance Creek Basin in the area is geologically simple. <br /> The northeast flank is a northwest to southeast trending sub-basin and is defined to the northeast <br /> by the Axial Basin Anticline and to the southwest by the Danforth Hills Anticline. The center of <br /> the sub-basin is defined by the Collom Syncline.The axis of the Collom syncline, a downward fold, <br /> passes through the permit area as shown on the Geology Map (Exhibit A3-3 and A3-4). Bedding <br /> orientation, as measured on surface outcrops, generally has a strike of N 70' W and is <br /> characterized by dips from nearly horizontal to as much as 20' to the north. Southward, the <br /> structure is influenced by the Elkhorn Syncline and a change in attitude of the structure occurs <br /> resulting in an eastward dip and nearly north-south strike. Local deviations in this general trend <br /> are the result of discontinuous minor folds resulting from differential compaction. <br /> During geologic mapping for the mine permit,there was no evidence of faulting in the rock units <br /> within the mining area;however,some linear features that may be fault controlled were observed <br /> on aerial photographs of the property. Such lineations may also be related to joints (fractures <br /> without appreciable movement) in the rock.Three major joint trends that generally coincide with <br /> 7 <br />