Ferques Fm., Gris Mbr., vicinity of Ferques, Bas-Boulonnais (Devonian of France)

Where: France (50.8° N, 1.8° E: paleocoordinates 22.1° S, 3.5° E)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Ancyrognathus triangularis conodont zone, Gris Member (Ferques Formation), Frasnian (382.7 - 372.2 Ma)

• triangularis conodont zone. JA: originally entered as Frasnian, but the triangularis zone is early Famennian. PJW: Palmatolepis triangularis is Famennian, but Ancyrognathus triangularis is Frasnian.

• member-level stratigraphic resolution

Environment/lithology: marine; limestone

• "The Blacourt Formation is a compact, massive bedded, black fossiliferous marine limestone, with argillaceous layers and some small reefs in the Griset Member. The lower [Cambreseque] and upper [Patures] member of the Beaullieu Formation are mainly terrigenous ["shale" mentioned in figure caption], except for its lowest beds, the so-called Cedule Limestone. The middle [Noces] member consists of dolomite lenses, passing upward into shales, and to a reef build-up capped by fossiliferous limestones. The base of the lower [Fiennes] member of the succeeding Ferques Formation is a biostromal dolomite overlain by yellow, then brownis-dark dolomite and dolomitic sandstones. These are overlain by the fully marine fossiliferous Ferques Limestone. The lower part of the [second-from-bottom] Bois Member and the upper part of the [third-from-bottom] Parisienne Member are biostromal. In the upper [Gris] member, sediments are more argillaceous..."

Size class: macrofossils

Primary reference: P. Morzadec, D. Brice, C. Cygan, R. Feist, C. Majeste-Menjoulas, F. Paris, and P. R. Racheboeuf. 2000. The Devonian of France: a tentative tie with the GSSP of the Devonian stages. Courier Forschungs-Institut Senckenberg 225:115-129 [M. Foote/M. Foote/M. Foote]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 38691: authorized by Michael Foote, entered by Michael Foote on 28.04.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

Anthozoa
 Auloporida - Thecostegitidae
Thecostegites bouchardi2 tabulate coral
 Auloporida - Aulocystidae
"Plexituba" ? cucullina2 tabulate coral
Strophomenata
 Orthotetida - Areostrophiidae
 Strophomenida - Chonetidae
 Strophomenida - Leptostrophiidae
Nervostrophia latissima1 Quenstedt 1871
 Strophomenida - Douvillinidae
Douvillina dutertrei1 Murchison 1840
 Productida - Productellidae
Productella subaculeata1 Murchison 1840
 Productida - Araksalosiidae
Rhynchonellata
 Rhynchonellida - Trigonirhynchiidae
 Orthida - Schizophoriidae
Schizophoria striatula1 von Schlotheim 1813
 Atrypida - Atrypidae
 Spiriferida - Adolfiidae
 Spiriferida - Cyrtospiriferidae
 Athyridida - Athyrididae