D-52-K, Walidiala Valley (Cambrian to of Guinea)

Where: Guinea (12.3° N, 12.4° W)

• Paleocoordinates: 86.2° S, 95.7° W (Wright 2013)

• coordinate estimated from map

• hand sample-level geographic resolution

When: Bowal Member (Nandoumari Formation), Tommotian to Tommotian (525.5 - 516.0 Ma)

• PJW: Bowal member belongs to the Nandoumari formation, not Nandoumari group! The member is Tommotian to Atdabanian in age, not just "Early Cambrian."

• member-level stratigraphic resolution

Environment/lithology: peritidal; lithified dolomite

• shallow subtidal to peritidal, algal-rich depositional environment
• The block is a light-tan, fine-grained calcareous dolostone showing millimetre-scale parallel laminations, which were probably of algal origin. In thin section, the texture of the sample is hypidiotopic dolomite with minor accessory pyrite and/or opaque organic matter along the grain-to-grain sutures. The outcrop from which the block came is composed of medium to massively bedded, fine- to medium-crystalline dolostone. The dolostone shows abundant millimetre-scale planar to wavy laminations, mudcracks, and disrupted bedding.

Size class: microfossils

Reposited in the USNM

Collection methods: chemical

Primary reference: S. J. Culver, J. Pojeta, and J. E. Repetski. 1988. First record of Early Cambrian shelly microfossils from west Africa . Geology 16:596-599 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 209267: authorized by Matthew Clapham, entered by Matthew Clapham on 28.04.2020

Creative Commons license: CC0 (CC0)

Taxonomic list

Show authors, comments, and common names
Brachiopoda
  -
? Brachiopoda indet.
Helcionelloida
 Pelagiellida - Aldanellidae
Aldanella attleborensis
Aldanella attleborensis Shaler and Foerste 1888
unclassified
  -
? Echinodermata indet.