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- 14 - <br />along the valley side is shown on Figs. 4 and 5. The faults are <br />usually downthrown on their northeastern side. Some backward rotation <br />has occurred in the fault blocks; however, bedding the mine has not <br />been rotated more than 10o from its pre -fault attitude inmost <br />areas. Displacements along the faults generally are from a few feet <br />up to a few tens of feet. Thick breccia zones and slickensided clay <br />gouge is commonly associated with the faults. In addition to <br />faulting, a shallow syncline is located west of the mine in a fault <br />bounded block between Monogram Mesa and the lease. <br />The uranium and vanadium deposits occur primarily in sandstone <br />beds in the upper part of the Salt Wash member of the Morrison <br />Formation. The Salt Wash member consists of alternating lenses of <br />fluvial sandstone and mudstone. At the mine site, the Silt Wash <br />member is overlain by the Brushy Basin member of the Morrison <br />Formation. The Brushy Basin member is predominantly a mudstone with <br />some sandstone, conglomeratic sandstone and limestone lenses. <br />A large landslide complex overlies the Brushy Basin and extends <br />downslope on to the Salt Wash, see Fig. 4. The landslide deposit is a <br />heterogeneous mixture of angular sandstone fragments in a sandy clay <br />matrix. The coarse rock fragments in the slide mass range from gravel <br />up to very large boulders. The exploratory holes and observations in <br />stream cuts indicate that the slide mass ranges from a few feet up to <br />about 40 feet thick. Signs of current slide activity were not <br />observed at the site or in the vicinity. To our knowledge, none of <br />the surface facilities at the mine or at adjacent mines have had <br />problems which could be associated with landslide activity. <br />