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• quartz, and several kinds of igneous rocks. The sand of the matrix was <br />largely derived from the Mesa Verde Formation, from which it was eroded <br />by Early Tertiary streams, and deposited chiefly in and around the <br />channels of those streams. The Ohio Creek Conglomerate is erradic and <br />locally absent, though in places it is as much as 200 feet thick. Where <br />the pebbles are scattered or lacking the Ohio Creek Conglomerate is <br />difficult to separate from the underlying Mesa Uerde Formation. <br />Wasatch Formation <br />The Wasatch Formation lies unconformably on the Ohio Creek Conglomerate, <br />or, where the Ohio Creek Conglomerate is lacking, on sandstone and shale <br />of the Mesa Verde Formation. It is comprised principally of course red <br />conglomerate sandstone and dark red to maroon sandy shale. Locally, an <br />abundance of epidote and other ferrous silicates produces a greenish <br />color. The strong coloring of the Wasatch Formation contrasts sharply <br />with that of the light-colored Ohio Creek Conglomerate and with the <br />• sandstone of the Mesaverde Formation. Conglomerate and sandstone <br />predominate in the lower 100 feet of the Wasatch Formation. Several <br />boulders of scoriaceous basalt, as much as 2 and one-half feet in <br />diameter are present and smaller pebbles of chert, jasperoid quartz, and <br />a variety of igneous and metamorphic rocks are widely distributed. <br />Above the conglomerate and sandstone zone, red and green shale and silt <br />are predominate. <br />Structure <br />The structural geology of the permit and adjacent area appears to be <br />quite simple. The sedimentary strata of the Mesaverde Formation are <br />relatively flat line with an average regional dip of 3.5 degrees to the <br />north-northeast. Local dips of up to 5 or 6 degrees can be found. No <br />faults have been mapped within the permit area or adjacent area. The <br />generalized geologic structural and stratigraphic setting of the area is <br />shown on the Regional Geology Map (Map 5), and Figure 2, Generalized <br />. Stratigraphic Column. The site specific stratigraphy is described in <br />2.04-18 <br />