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Walidiala Valley [Nandoumari Fm] (Cambrian to of Senegal)

Where: Senegal (12.3° N, 12.4° W: paleocoordinates 75.3° S, 148.6° E)

• basin-level geographic resolution

When: Bowal / Fougons Member (Nandoumari Formation), Tommotian to Tommotian (530.0 - 516.0 Ma)

• member-level stratigraphic resolution

Environment/lithology: marine; lithified, cherty/siliceous dolomite and siltstone

• the fosils are from a sequence of undeformed and unmetamorphosed sedimentary rocks. the fossiliferous units are characterized by mm-cm thick, sharp erosionally based, flat-topped graded beds. no evidence of bioturbation and no hummocky cross-beds. the thinning/fining upwards from the bowal to fougon is interpretted as an increase of water depth/distance from the shoreline. the calcitic specimens are collected above the Bowal memeber (east side of walidiala valley) and from a purple sandstone 2m above the chert beds in the fougon member (west side of walidiala valley).

Size class: macrofossils

Preservation: replaced with calcite, replaced with silica, replaced with phosphate

Collection methods: bulk, chemical,

Primary reference: S. J. Culver, J. E. Repetski, J. Pojeta, Jr. and D. Hunt. 1996. Early and Middle (?) Cambrian metazoan and protistan fossils from West Africa. Journal of Paleontology 70(1):1-6 [M. Patzkowsky/P. Borkow/J. Alroy] more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 7790: authorized by Mark Patzkowsky, entered by Phil Borkow on 02.06.2000

Creative Commons license: CC BY (attribution)