2016-11-18_PERMIT FILE - C1981019A (7)

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RULE 2 PERMITS Starting on the north end of the permit area, the Axial Basin anticline is an asymmetrical fold, the axis of which trends north 60° west, with strata dipping (inclining) steeper on the south side of the axis than on the north. The rocks of the broad anticline have not been stressed sufficiently to cause them to break severely, but a few discontinuous normal faults trending primarily parallel to the anticlinal axis are found in the area. The south flank of the anticline has several secondary folds trending subparallel and at approximate right angles to the main anticlinal axis. The axis of the Collom syncline, a downward fold approximately parallel with the Axial Basin Anticline, passes north of the existing Colowyo mine and permit revision area. Bedding orientation, as measured on surface outcrops, has a strike of around N 70° W. Dips on the shared limb with the Axial Basin anticline can exceed 45°, but are normally between 25° and 35° and dip to the south. The south flank of the syncline has dips between 5° and 20° to the north (Map 7A). Near the county line of Moffat and Rio Blanco Counties (which traverses the southern portion of the permit revision area), a small anticline trending northeast is present. This unnamed anticline is an offshoot of the Danforth Hills anticline and Wilson Creek Dome to the south and west. Dips on the south flank of this small anticline are between 3° and 20° to the southeast. This anticline is associated with a small syncline located between it and the Danforth Hills anticline. The synclinal axis is located in the West Fork of the Good Springs Valley. South and west of the permit revision area is the Wilson Creek Dome, part of the Danforth Hills anticline. A producing petroleum reserve, the dome is capped by the Iles Formation. This uplift has caused the Lower Wilson area to be uplifted and only the bottom 700 feet of the Williams Fork is present. The beds in this area have a strike to the northwest with dips to the northeast of approximately 7°. The existing mine and permit revision area are affected on the east by an unnamed syncline that is aligned with the West Fork of Good Spring Creek. This fold has a northeast strike and the western flank of the syncline causes the beds on the east side of the South Taylor and existing mine area to dip to the southeast. These beds increase their dip as the axis of the syncline is approached in the South Taylor area. During past photogeological studies and field activities, the possibility of faulting in the rock units of the Lower Wilson area has been identified, but no faults have been identified in the field or during drilling. Linear features, which are controlled by the Wilson Dome, are also observed on aerial photographs of the Lower Wilson area property. Such lineations are related to joints (fractures without appreciable movement) in the rock. Three major joint trends that generally coincide with these lineations were observed within the proposed mining areas. These are nearly vertical or vertical and strike approximately north 70° west, north 45° west, and north 30° east. In surface exposures, the sandstone outcrops exhibit these joints more readily than the highly oxidized and weathered coal beds. However, both have undergone similar stresses and have developed similar readjustment features that are apparent in the subsurface. South Taylor/Lower Wilson — Rule 2, Page 13 Revision Date: 11/18/16 Revision No.: MR -163