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<br />A detailed study of aerial photographs revealed a considerable number of lineaments (lineaz features) <br />throughout the mine azea. The linear features observed included topographic alignments, vegetative <br />' alignment, tonal and color alignments. The only alignment identified in the field to date is a well <br />defined joint pattern which strikes North 65 degrees West. <br />t Observations in the field include slight rolls or folds in the strata with low relief. There are occasional <br />outcrops with strata exhibiting dips of up to 30 degrees. These dips are confined to small azeas and <br />' appeaz to be the result of differential compaction around lenticular sandstones (channel sandstones). <br />' 3.2 General Stratigraphy <br />The rocks exposed throughout the Deserado Mine area are within the Mesaverde Group of Upper <br />' Cretaceous age. These sedimentary beds are well exposed as a southwest facing escarpment along the <br />flank of the Rangely anticline and along the course of Scullion Gulch and its tributazies. <br />Gaskill and Hom (1959) in an unpublished report on the northeast Rangely coal field descrbe the <br />Mesaverde as "lazgely composed of yellowish to very light gray, massive, thin bedded and flaggy, <br />' angular to subangulaz, very fine to fine grained quartz sandstone, interbedded with sandy gray shale, <br />siltstone and mudstone, cazbonaceous shale, coal, and occasional thin ofren concretionary lenses of limey <br />sandstone and sandy limestones." They state that it appears to be divisible into at least two units. <br />The Mesaverde Group in the mine area has not been previously subdivided on a formational basis. <br />' Throughout much of northwestern Colorado the Mesaverde has been divided into the basal lies <br />Formation, and the overlying Williams Fork Formation, with the contact lying atop the Trout Creek <br />Sandstone Member of the Iles Formation. The Trout Creek Sandstone has been tentatively identified <br />east of the mine azea near Elk Springs. Mapping by H.L. Collins (1971) within the Rangely Quadrang- <br />le,identifies the Trout Creek Sandstone equivalent east of Douglas Creek about three miles southeast <br />' of Rangely and seven miles south of the mine azea. <br />' It is generally recognized that the principal coal zone within the Mesaverde Group occurs neaz the base <br />of the Williams Fork Formation and just above the Trout Creek Sandstone. Coals within the Iles <br />Formation aze known to be thin and laterally discontinuous. The lithology of the Iles Formation is <br />' dominated by laterally continuous sandstones and shales. <br />' Based on this information and on data gathered by Western Fuels during field mapping and exploratory <br />drilling, the strata exposed in the mine azea have been subdivided into three zones. ]n ascending order <br />1 <br />r 9 <br /> <br />