7-11 Mine Dark Shale (Carboniferous to of the United States)

Where: Columbiana County, Ohio (40.6° N, 80.6° W: paleocoordinates 7.0° S, 17.6° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Dark Shale Member (Mahoning Formation), Podolskian to Podolskian (311.4 - 300.2 Ma)

• Section (Figure 1) on p. 48.

• group of beds-level stratigraphic resolution

Environment/lithology: mire or swamp; pyritic, black, gray, argillaceous, carbonaceous shale

• A large portion of the lake sediments consisted of stagnant carbonaceous muck
• finely laminated dark gray to black organic shales...The fine-grained argillaceous matrix....The occurrence of abundant plant remains, permineralized by FeS2 (pyrite).

Size class: macrofossils

Preservation: adpression, permineralized, replaced with pyrite

Primary reference: M. A. McComas. 1988. Upper Pennsylvanian compression floras of the 7-11 Mine, Columbiana County, northeastern Ohio. Ohio Journal of Science 88:48-52 [H. Sims/S. Ostrowski]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 11188: authorized by Hallie Sims, entered by Summer Ostrowski on 23.07.2001, edited by Alistair McGowan and Jason Cassara

Creative Commons license: CC BY (attribution)

Taxonomic list

Neuropteris heterophylla
"Neuropteris heterophylla" = Imparipteris heterophylla
"Neuropteris heterophylla" = Imparipteris heterophylla Brongniart 1825
  - Cordaitaceae
Artisia sp. Sternberg 1838
 Coniferales -
Samaropsis sp. Göppert 1864
 Cordaitanthales -
 Pinales -
Gomphostrobus sp. Marion 1890
Sigillariostrobus sp. Schimper 1870
Aphlebia sp. Presl 1838
May be assignable to either a filicopsid or a pteridosperm
  - Neuropteridae
Spiropteris sp. Schimper 1869
May be assignable to either a filicopsid or a pteridosperm
 Peltaspermales - Peltaspermaceae
 Radiatopses - Medullosaceae
Neuropteris scheuchzeri
Identification tentative due to poor preservation
 Cordaitales -
Cordaianthus spp. Grand'Eury 1877
Walchiostrobus sp. Florin 1940
Walchia sp. Sternberg 1825
 Lepidodendrales - Lepidodendraceae
  - Sigillariaceae
Sphenopsida indet.
Calamitean diaphragm
 Equisetales - Equisetidae
Calamites suckowii Brongniart 1828
Identification tentative due to poor preservation
 Marattiales - Marattiidae
Asterotheca sp. Presl 1845
Ptychocarpus sp. Weiss 1869
 Filicinae -
Pecopteris candolleana
Identification tentative due to poor preservation
"Alethopteris sp." = Pecopteris (Alethopteris) Sternberg 1825
Lycopsida indet.
Sigillarian cone axis
Cyperites sp. Lindley and Hutton 1832