Late Paleozoic stratigraphy of central Cochise County, Arizona

Abstract

____-_-____________________._ Introduction. ______________________________________ Priorwork_________________________________________ Mississippian rocks_________________________________ Escabrosa limestone___________________________ Distribution and general character.___________ Stratigraphy. ______________________________ Thickness________________________________ Representative sections____________________ Fauna and correlation of the Escabrosa limestone, by James Steele Williams. _________ __ Collections from Tombstone Hills_______ Collections from Dragoon Mountains____ Collections from Gunnison Hills __________ Collections from other localities________ Character and age of the fauna___________ Register of U. S. Geological Survey collections from localities not in stratigraphic sections described in this report_______ Pre-Black Prince disconformity_________________ Black Prince limestone________-_____-___________ Name.____________________________________ Distribution and topographic expression-______ Stratigraphy-______________________________ Representative sections,_____________________ Thickness________________________________ Fauna and correlation of the Black Prince limestone, by James Steele Williams. _________ Collections from Gunnison Hills. _________ Collections from Little Dragoon Mountains. Character and age of the fauna.._________ Register of U. S. Geological Survey collections from Black Prince localities not in stratigraphic sections described in this report.- ..- .-_______________________ Mississippian-Pennsylvanian disconformity___________ Pennsy 1 vanian and Permian rocks.___________________ Naco group._________________________________ Name and subdivisions_-____________________ Horquilla limestone_________________________ Name.________________________________ Distribution and topographic expression___. Stratigraphy ___________________________ Earp formation___________________________ Name and type locality_______________ Distribution and topographic expression. __ Stratigraphy ___________________________ Representative sections__________________ Thickness____________________________ Conditions of deposition.________________ Colina limestone_________ T ________________ Name_____________________________ Distribution and topographic expression. __ Pennsylvanian and Permian rocks-Continued Naco group-Continued Colina limestone-Continued Stratigraphy.

U-Pb isotope ages of granitic plutons near Cananea, Sonora

“…This work was complemented by two papers written by Gilluiy (1956) and Gilluly, Cooper and Williams (1954) which deal with the general geology and late Paleozoic stratigraphy and central Cochise County. More recent research carried out by Cooper and Silver (1964) in the Dragoon Quadrangle, provides detailed data pertaining to the older Precambrian rocks as well as the general geology.…”

Paleozoic stratigraphy of the southern part of the Mule Mountains, Arizona

“…The fossils, age, and correlation of the Naco Group in the nearby Tombstone area were discussed in detail by Gilluly, Cooper, and Williams (1954). The few megafossils collected during the present investigation, which were examined by E. L. Yochelson and J. T. Dutro, Jr. (written commun., 1961), confirm their conclusions on the age of the Naco Group but add very little to the detail.…”

The Mississippian and Pennsylvanian (Carboniferous) systems in the United States

“…Girty's studies also led to the recognition that strata lumped into original Naco lim,estone contained Permian (Hueco) forms. Gilluly, Cooper, and Williams (1954) raised the Naco to group status 3!nd differentiated six formations in central Cochise County. Their Pennsylvanian representatives were the Horquilla Limestone (Atokan to mid-Virgilian ?)…”