Loc. 6. USGS 19959. Slump 457m down s. bank of Middle Fork of Little Fork River (Carboniferous of the United States)

Also known as USGS Locs: 28540-PC. 2.3 km ne of abandoned community of Elba

Where: Van Buren County, Arkansas (35.8° N, 92.5° W: paleocoordinates 12.4° S, 34.0° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Imo Formation, Serpukhovian (330.9 - 323.2 Ma)

• Elvirian (E2b-c); late Chesterian is Serpukhovian according to Mii et al. 1999 (GSA Bull 111:960-973)

• bed-level stratigraphic resolution

Environment/lithology: offshore; lithified, concretionary, black, gray, sandy grainstone and shale

• "The environment of deposition...relatively shallow water, low energy offshore area undergoing slow continuous deposition of terrigenous clay with periodic higher-energy incursions of carbonate sediments."
• ...as much as 104 m of dark-gray to black, fissile, clay shale w/ numerous, large, bright-red, orange, or brown concretions. ...the lower 36 m...contains thin limestones, sandstones, and conglomerates.

Reposited in the OSU

Primary reference: R. D. Hoare, M. J., I.I.I. Heaney, and R. H. Mapes. 1989. Bivalves (Mollusca) from the Imo Formation (Mississippian, Chesterian) of North-Central Arkansas. Journal of Paleontology 63(5):582-603 [P. Wagner/P. Wagner]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 69284: authorized by Pete Wagner, entered by Pete Wagner on 23.02.2007

Creative Commons license: CC BY (attribution)

Taxonomic list

• Crinoids, bryozoans, brachiopods, bivalves, corals, nautiloids also present.
Gastropoda
 Murchisoniina - Gosseletinidae
"Glabrocingulum (Glabrocingulum) quadrigatum" = Glabrocingulum quadrigatum, Glabrocingulum (Glabrocingulum) parasolum, "Glabrocingulum (Glabrocingulum) binodosum" = Glabrocingulum binodosum
"Glabrocingulum (Glabrocingulum) quadrigatum" = Glabrocingulum quadrigatum Sadlick and Nielsen 1963 snail
"Glabrocingulum (Glabrocingulum) binodosum" = Glabrocingulum binodosum Sadlick and Nielsen 1963 snail
 Murchisoniina - Soleniscidae
Bivalvia
 Pectinida - Aviculopectinidae
Imoella obscura Hoare et al. 1989 scallop
 Ostreida - Pterineidae
Leptodesma sp. Hall 1883 oyster