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">!f~ ~Jj Reservoir Geology. The greater part of the reservoir basin is within the Carboniferous Red Beds, which here dip 100 downstream and consist of alternating strata of soft, impervious ;> shales and sandstones that are (or have been stained) a deep maroon color. A~ the upper end of the reservoir basin a hard limestone appears from below the shales and sandstones, but it outcrops on only a small area, being generally mantled by moraine and outwash deposits and should not be the cause of deep losses. No faults er other disturbances are evident. The normal river fill, over 100 feet thick in deeper parts of the valley, extends as high as the present stream bed and is quite pervious due to the lack of silt and fines and to the presenc~ of many boulders. The normal morainal deposit, somewhat, reworked, lies .,~ U~;; {.~~.:.. '-u.':.' upon ~he river fill to an average depth of 50 feet. It is less per- vious than the river fill below cut not so tight as the deep parts of the outwash talus which covers it. The outwash material lying in fans a~ the mouths of present tributary drainage channels contains a mixture of morainal material and eroded material, largely red clay, from the exposed Red Bed strata, and is compact and impervious. The water table is tributary to the stream and loss from the reservoir would be confined to percolation under the dam. Damsite (}eology, The damsite, near the south line of sec- tion 17, T. 36 N" R, 7 W., N.M,P.M., lies at the lower end of a wider, flat portion of the river valley, and just above a narrow gorge that extends two miles downstream. The river flows at the top of the river gravels in a shallow, narrow trench 50 feet deep cut in .;.. 50