River Yarrow, Gastrioceras cumbriense Marine Band, shale Unit 2 (Carboniferous to of the United Kingdom)

Also known as Unit 2, the advance shales, River Yarrow Chorley, Lacanshire

Where: England, United Kingdom (53.7° N, 2.7° W: paleocoordinates 1.2° S, 6.1° E)

• coordinate based on political unit

• outcrop-level geographic resolution

When: Pendleian to Pendleian (330.9 - 318.7 Ma)

• The Gastrioceras cumbriense Marine Band generally does not exceed 60cm in thickness. The band is split into five units, the lower barren shales (Unit 1), the advance shales (Unit 2), the acme shales (Unit 3), the retreat shales (Unit 4), and the upper barren shales (Unit 5).

• group of beds-level stratigraphic resolution

Environment/lithology: marine; lithified, gray siltstone

• unit 2: At the River Yarrow locality the red mudstone is rapidly replaced upwards by a hard, dark grey-green siltstone with an abundant marine fauna dominated by gastropods and fish debris. The amount of fragmentation is high and the most mechanically resistant elements of the fauna predominate, indicating deposition in an area swept by currents, whereas the abundant fish debris indicates the condensed nature of this deposit. The evidence from this locality and from the thick sequence at Winter Hill indicates the earlier establishment of marine conditions in the west of the area.

Size class: macrofossils

Collection methods: bulk,

Primary reference: P. B. Wignall. 1987. A biofacies analysis of the Gastroceras cumbriense marine band (Namurian) of the central Pennines. Proceedings of the Yorkshire Geological Society 46(2):111-121 [J. Alroy/C. Simpson/C. Simpson]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 41184: authorized by John Alroy, entered by Carl Simpson on 07.07.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Gnathostomata
  -
Osteichthyes indet.
Osteichthyes indet. bony fish
Palaeoniscid scales
Chondrichthyes
  - Listracanthidae
Listracanthus sp.
Listracanthus sp. Newberry and Worthen 1870 elasmobranch
Spines
Lingulata
 Lingulida - Lingulidae
Lingula mytilloides
 Lingulida - Discinidae
Orbiculoidea sp.
Orbiculoidea sp. d'Orbigny 1847
Cephalopoda
 Goniatitida - Gastrioceratidae
Gastrioceras spp.
Gastrioceras spp. Hyatt 1884 ammonite
Juvenile
Gastropoda
  -
Gastropoda indet.
Gastropoda indet. Cuvier 1795 snail
Small
 Bellerophontida -
Bellerophontida indet.
Bellerophontida indet. Ulrich and Scofield 1897 snail
Bivalvia
 Arcida - Parallelodontidae
Grammatodon sp.
Grammatodon sp. Meek and Hayden 1860 clam