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sandstone dominated portion of the Mesaverde Group is exposed as nearly vertically dipping <br />east/west trending hogback ridges north of the mine permit area along the north limb of the syncline. <br />The strike of the coal beds within the mine permit application area is approximately N46°W. <br />Early investigation indicated the possible presence of minor normal faulting in lease C-023703. <br />However, the intensive field mapping and exploration drilling programs carried out to date have found <br />no evidence of faulting. <br />11.6.3 Coal Geology All mining and related mining activity associated with the Deserado Mine will <br />be performed within or upon rocks of the Mesaverde Group. The carbonaceous zone containing the <br />coal beds of interest occupies the basal 200 to 300 feet of the Lower Williams Fork Formation. The <br />B and D coal seams are contained in a 25- to 70-foot interval occurring 10 to 40 foot above the tap of <br />the B Horizon Sandstone. ARhough coals are prevalent throughout the rest of the carbonaceous zone, <br />they are commonly too thin or of too little lateral extent to be considered mineable. <br />Drilling programs conducted to date, have identified seven (7) coal seams traceable throughout all or <br />part of the mine permit area. These seven seams occur in the basal 200 to 300 feet of the Lower <br />Williams Fork Formation. The lithology of the coal bearing zone is predominately siltstone, shale, <br />carbonaceous shale and coal interbedded with thin, discontinuous, often calcareous sandstone units. <br />The siltstones and sandstones commonly contain abundant carbonaceous material. The lower limit <br />of the zone is marked by the B Horizon sandstone. The underlying Iles Formation is characterized <br />by thick (20 to 40 feet) sandstones and occasional very thin carbonaceous shales or coals. Overlying <br />the coal bearing zone, the Upper Williams Fork is likewise characterized by a marked change to <br />coarser grained sediments. Very thick, lenticular, argillaceous, sandstone units are predominant. <br />Coals, where present, are thin and laterally discontinuous. The seven (7) apparently distinct coal <br />seams, in ascending order, are: <br />• B Seam <br />• D Seam <br />• E Seam <br />• F Seam <br />• G Seam <br />• H Seam <br />• J Seam <br />In addition to the seven (7) seams listed above, there has also been identified a thin somewhat <br />continuous coal located immediately below the B Horizon in the Iles Formation. This coal is referred <br />to as Iles Seam, Map 4 shows the location of seven (7) cross sections. Illustrations 36, 37 and 38 <br />show these seven typical stratigraphic cross sections, (structure is shown below each section) and <br />• illustrates the stratigraphic relationship of the seven seams in the Lower Williams Fork plus the Iles <br />Seam. Seven (7) typical geophysical logs are included in Illustrations 14, 15 and 16. Only the B and <br />(Permit Renewal #3 1/99) II.B~ <br />