Bulletin, Izdaje 52–55

alluvium Anticline aquifer artesian bentonitic Big Belt Mountains Blackleaf Formation bloat Bootlegger boulders Cascade Butte Cascade County Cascade-Ulm area Cemented gravel chert chlorite clay and shale Cobban Colorado Group contains dark gray Depth dikes dips dune sand E D Tca E D,S feet thick Ferdig firing Flood Member Flows folds Glacial Lake Missoula Gravel and sand hardpan Kalispell Kalispell Valley Kevin Kootenai Kootenai Formation map area Marias River Marias River Formation material Maughan miles mineral Mines and Geology Missouri River Montana Montana Bureau N N Tca Oregon outcrop pebbles percent plagioclase plasticity poorly indurated quartz deposit red HS rock Sample Sand and gravel sandstone sandstone units Sandy shale silica sills silt siltstone Smith River springs Square Butte stratigraphic surface Taft Hill Taft Hill-Vaughn Telegraph Creek U.S. Geological Survey upper Virgelle Formation weathers light gray