Nearshore zone +1, Johns Mountain, Dunaway Gap Road (Ordovician of the United States)

Where: Chattooga County, Georgia (34.5° N, 85.1° W: paleocoordinates 29.6° S, 66.2° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Caradoc (458.4 - 449.5 Ma)

• No information given.

Environment/lithology: shallow subtidal; red, yellow siltstone and yellow sandstone

• \"The upper one-fourth of the zone is composed of red to yellow siltstone with an occasional mottled bed showing purplish splotches. A fine-grained, buff-colored sandstone occurs about 45 feet below the top of the zone. The middle part of the zone is composed of red siltstone with a bed of conglomeratic sandstone 2 feet thick at its base. The lower half of the zone is composed of silty limestone. About 5 feet above the base occurs a fossil horizon containing both identifiable and unidentifiable fragments of brachiopods and bryozoa. The lowest member of the zone is a bed of medium-grained yellowish sandstone about 2 to 4 feet thick. In some sections small pebbles randomly scattered through it give it a loose conglomeratic texture."

Size class: macrofossils

Primary reference: A. T. Allen and J. G. Lester. 1957. Zonation of the Middle and Upper Ordovician strata in northwestern Georgia. Georgia State Division of Conservation, the Geological Survey Bulletin 66:1-104 [S. Holland/T. Hanson/T. Hanson]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 32458: authorized by Steven Holland, entered by Tori Hanson on 01.07.2003

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Strophomenata
 Strophomenida - Sowerbyellidae
Sowerbyella sp.
Sowerbyella sp. Jones 1928
Rhynchonellata
 Rhynchonellida - Ancistrorhynchidae
Ancistrorhyncha costata
Ancistrorhyncha costata Ulrich and Cooper 1942
Ulrich & Cooper
 Rhynchonellida - Orthorhynchulidae
Orthorhynchula linneyi
Orthorhynchula linneyi James 1881
James
 Rhynchonellida - Rhynchotrematidae
Rhynchotrema minnesotensis, Rhynchotrema increbescens
Rhynchotrema increbescens Hall 1847
Hall
 Rhynchonellida - Camarotoechiidae
Camarotoechia sp.
Camarotoechia sp. Hall and Clarke 1893
 Atrypida - Anazygidae
"Zygospira recurvirostris" = Anazyga recurvirostra
"Zygospira recurvirostris" = Anazyga recurvirostra Hall 1847
Hall