Rapid City - Skyline hogback area Sections in end near St. Cloud Street. A. Roadcut in upper Fall River N side St. measuring up from Festone layer within vzr zone, 1 5.6 Claystone silty, some clayey siltstone locally silt., grey locally with ten crest. Then to impreg irveg layers silt - some may be Festone. Clay stone has carb flecks. At base is 0.6 Festone, sandy, weathers purplish brown. 2 3.0 Sandstone, fine grained, in thin beds with interbeds silty claystone locally spherulitic. Laterally SS thins out into the clstn except for few thin beds, Weather's lite pinkish brown. 3 2.6 Chiefly siltstone and clay siltston, carb flecks massive, lite gray, loc pink ston, spotty zones spherulitic.. Ites some sandy zones, grades to units above & below. 11