Changes in stratigraphic nomenclature by the U.S. Geological Survey, 1971

Abstract

1971.) Kenilworth and Sunnyside Members of Young (1955) of Blackhawk Formation adopted. Formation includes (ascending): Aberdeen, Kenilworth, lower mudstone, Sunnyside, and upper mudstone members. (Maberry, 1971.) Blackrock Canyon Limestone adopted. Same formation as Blackrock Limestone of Anderson (1928). Overlies Pocatello Formation (not new); underlies Papoose Creek Formation (new). (Crittenden and others, 1971.) Age changed from Devonian(?) to Late Ordovician. (Zartman and Marvin, 1971.) New Providence Shale reinstated in central Kentucky as basal member of Borden Formation. Nancy Member restricted to more silty, nonplastic shale within Nancy Member of previous usage. (Taylor and Lewis, 1971.) In its type area, Wasatch Mountains, Brigham is raised to group rank. Includes (ascending): Caddy Canyon(?) Quartzite (new), Inkom(?) Formation (new), Mutual Formation, Browns Hole Formation (new), and Geertsen Canyon Quartzite (new). Brigham Quartzite remains in good usage in south easternmost Idaho; Brigham restricted from usage in Pocatello area. (Crittenden and others, 1971.) Brodhead Creek Member of Willard (1938) adopted as upper of three members of Marcellus Shale. Overlies Stony Hollow Member (not new). (Alvord and Drake, 1971.) Bromley Shale of Bassler (1906) adopted as Bromley Shale Member of Point Pleasant Formation. (Luft, 1971.) Browns Hole Formation adopted; assigned to Brigham Group (newly revised). Overlies Mutual Formation; underlies Geertsen Canyon Quartzite (new). (Crittenden and others, 1971.) Buttermilk Falls Limestone of Willard (1939) adopted. Overlies Schoharie Formation; underlies Marcellus Shale. (Alvord and Drake, 1971.) Cabrillo Formation adopted as uppermost formation of Rosario Group (not new); overlies Point Loma Formation (new). (Kennedy and Moore, 1971.) Caddy Canyon Quartzite adopted. Overlies Papoose Creek Formation (new); underlies Inkom Formation (new). In Huntsville area of northern Utah only, tentatively assigned as lowermost formation of Brigham Group (newly revised), overlying Kelley Canyon Formation (new) and underlying Inkom(?) Formation of Brigham Group. (Crittenden and others, 1971.) Age changed from Oligocene(?) to Oligocene. (Wells and others, 1971.) Cambalache Formation adopted. Overlies Hato Puerco Formation; underlies Can6vanas Formation (new). Toma de Agua Vitrophyre Member (new) adopted with restricted occurrence at top of Cambalache. (Seiders, 1971.) Camelback Mountain Formation adopted. Overlies Mutual Formation; underlies Gibson Jack Formation (new). (Crittenden and others, 1971.) Can6vanas Formation adopted. Overlies Cambalache Formation (new); underlies Martin Gonzalez Lava. (Seiders, 1971.) Age changed from late(?) Paleozoic to Late Ordovician. (Zartman and Marvin, 1971.) Carter Sandstone Member adopted; underlies and overlies two unnamed shale members of Pierre. (Izett and others, 1971.) Carter Caves Sandstone adopted as uppermost Mississippian formation (at Mississippian-Pennsylvanian systemic boundary) in northeastern Kentucky. (Englund and Windolph, 1971.) De...