Thick lava flows, welded tuffs, glacial QUATERNARY _CENOZOIC_ deposits, and hot-spring deposits 2-3 Pliocene, Miocene, and Oligocene rocks not known to be present 37-38 Absaroka volcanic Absaroka volcanic TERTIARY rocks rocks (Eocene) 53-54 Volcanic and Pinyon Conglomerate sedimentary (Paleocene and rocks (largely Cretaceous) eroded away before Absaroka volcanic rocks were deposited) 65 Landslide Creek Fm Harebell Formation CRETACEOUS _MESOZOIC_ Everts Formation (Eroded away before Harebell was deposited) Eagle Sandstone Bacon Ridge Sandstone Telegraph Creek Fm ″ Cody Shale Cody Shale Frontier Formation Frontier Formation Mowry Shale Mowry Shale Thermopolis Shale Thermopolis Shale Kootenai Formation Cloverly Formation 136 Morrison Formation Morrison(?) Fm JURASSIC Swift Formation Sundance Formation Rierdon Formation ″ Sawtooth Formation Gypsum Spring Fm 190-195 Woodside & Chugwater Formation TRIASSIC Thaynes(?) Formations Dinwoody Formation Dinwoody Formation 225 Shedhorn Sandstone Phosphoria Fm and PERMIAN _PALEOZOIC_ related rocks 280 Quadrant Sandstone Tensleep Formation PENNSYLVANIAN Amsden Formation Amsden Formation Mission Canyon Madison Limestone MISSISSIPIAN Limestone Lodgepole Limestone ″ 345 Three Forks Fm Darby Formation DEVONIAN Jefferson Formation ″ Bighorn Dolomite (Not exposed, ORDOVICIAN except for isolated outcrops of some formations in Falls River area, in southwestern part of park) 500 Snowy Range Fm ″ CAMBRIAN Pilgrim Limestone Park Shale Meagher Limestone Wolsey Shale Flathead Sandstone 570 Gneiss and Schist (Not exposed) PRECAMBRIAN 2,700