Sequence 2
Sequence 2
Devonian to Ordovician
Includes the following units of Ross (1963, 1965, 1967) and Stone and others (1989, 2000, 2009): Devonian Lost Burro Formation (mainly limestone and marble, some dolomite and sandstone); Devonian and Silurian Hidden Valley Dolomite (massive dolomite with minor sandy dolomite and sandstone); Devonian(?) and Silurian Vaughn Gulch Formation (bioclastic limestone and argillaceous limestone); Devonian(?) and Silurian Sunday Canyon Formation (limy shale, shale, and lesser limestone); Silurian and Ordovician Ely Springs Dolomite (thick-bedded dolomite characterized by chert nodules and lenses); Ordovician Johnson Spring Formation (mixed quartzite, dolomite, and limestone); Ordovician Barrel Spring Formation (shale, mudstone, siltstone, limestone, and impure quartzite); Ordovician Eureka Quartzite (fine- to medium-grained quartzite and basal argillite); Ordovician Badger Flat Limestone (laminated dolomite); Ordovician Pogonip Group (thick-bedded dolomite and limestone, with chert and sandy limestone in the upper part, and shale and mudstone in the lower part); and Ordovician Al Rose Formation (siltstone, shale, and mudstone, with lesser limestone).