70 CENOZOIC Neogene Pleistocene Bandelier volcanic ash, Man basalts, sand dunes, river gravels, glacial & lake beds. 1 my Pliocene Volcanic rocks of Mt. Mammals Taylor, early Valle Grande & Gila region; Santa Fe, Gila, and Ogallala Fms. 11 my Miocene 25 my Paleogene Oligocene Datil, Espinaso, and other volcanic rocks. 40 my Eocene Baca, Animas, Nacimiento, San Jose, Raton, Poison Canyon, Galisteo El Rito, Blanco Basin, & Cub Mountain Fms. 60 my Paleocene 160 MESOZOIC Cretaceous Upper sandstone, shale, & Dinosaurs coal. Mesaverde, Pierre, & Niobrara, Dakota Ss. and Mancos Sh. Volcanic rocks, limestone, sandstone, and conglomerate. 135 my Jurassic Morrison Fm., Summerville Fm., Zuni Ss., Todilto Ls. & gypsum, Entrada Ss. 180 my Triassic Wingate Ss., Dockum Fm., Chinle Fm., Santa Rosa Ss., Moenkopi Fm. 370 PALEOZOIC Permian Rustler Dolomite; redbeds Amphibians Castile gypsum, Salado Salt. Artesia Grp.—Capitan reef San Andres Ls.—Goat Seep reef Glorieta Sandstone Yeso Fm.—Bone Spring Fm. Abo Redbeds—Hueco Ls. 280 my Pennsylvanian Mostly limestone; beds of shale & sandstone; lenses of gypsum, salt, and coal. 310 my Mississippian Helms & Paradise Fms. Fish Rancheria Ls. Lake Valley & Escabrosa Lss. Arroyo Penasco & Tererro Fms. 345 my Devonian Percha Shale, Ouray Ls. northern dol., ss, and sh. erosion 400 my Silurian Fusselman Dolomite erosion 425 my Ordovician Montoya Dolomite Invertebrates El Paso Limestone Bliss 500 my Cambrian Sandstone erosion 1500+