PBDB Collection

Leptaena-Rugosatrypa Community, Noulette Fm., Noulette Borehole, Artois (Devonian of France)

Where: France (50.5° N, 2.5° E: paleocoordinates 25.9° S, 4.5° W)

• coordinate based on political unit

• local area-level geographic resolution

When: Noulette Formation (Lievin Group), Lochkovian (419.2 - 410.8 Ma)

• Lower part of the 'Calcaire d'Angres' sensu Barrrois et al. 1922), Lievin Group.

• formation-level stratigraphic resolution

Environment/lithology: marine; calcareous shale and sandstone

• General statement of Central Armorican trough during Llandovery through Lochkovian: "depositional patterns typical of a platform environment...Silurian is mainly an alternating succession of unfossiliferous sandstones and locally fossiliferous black shales...The arenaceous deposits are probably related to the eustatic regression and corresponding high sedimentation rate during the Pridolian and Lochkovian...Outside the A. Massif the Pridoli-Lochkovian succesion in Artois (boreholes) is characterized by shallow marine shales and limestones overlain by areanceous deposits that correspond to the Early Devonian transgression."

•For this Community: "Shells commonly disarticulated. The faunal and depostional characteristics suggest a quiet water environment on a muddy, calcareous bottom , with some episodic deposition of siltstone and fine-grained sandstone indicating sudden, high energy events. The fauna closely resemebles that of the Hollardina plana Community [PBDB coll. 26116] [differences are noted]...A deep BA 3 position is assigned to this community."

• General statement: "In Brittany there are two kinds of black shale and limestone deposits during the Llandovery to lowermost Devonian interval: (1) black shales (commonly described as sapropelites) are widespread in space and time and (2) black, micritic limestones or argillaceous limestones are restricted to two localities in the eastern part of the Armorican Massif. The black shales are very rich in organic matter and locally contain detrital mica, pyrite, and nodules..."

•For this community: "restricted to 10-15 m of drk, calcareous shale interbedded with thin layers of sandstone having wave crossbedding"

Primary reference: P. R. Racheboeuf. 1999. Lower Silurian to Lower Devonian communities from the Armorican Massif (western France) and Artois (northern France). In A. J. Boucot, J. D. Lawson (eds.), Paleocommunities--a case study from the Silurian and Lower Devonian 260-270 [M. Foote/M. Foote/P. Wagner]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 26119: authorized by Michael Foote, entered by Michael Foote on 04.10.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names

Crinoidea
-	Crinoidea indet. Crinoidea indet. Miller 1821 Sea lily
Bivalvia
Nuculanida - Malletiidae	Palaeoneilo sp. Palaeoneilo sp. Hall and Whitfield 1869 clam
Strophomenata
Strophomenida - Amphistrophiidae	Mesodouvillina (Mesodouvillina) triculta Mesodouvillina (Mesodouvillina) triculta
Strophomenida - Rafinesquinidae	Leptaena nassichuki Leptaena nassichuki Smith 1980
Rhynchonellata
Orthida - Dalmanellidae	Isorthis (Protocortezorthis) sp. Isorthis (Protocortezorthis) sp. Walmsley and Boucot 1975
Spiriferida - Delthyrididae	Howellella sp. Howellella sp. Kozlowski 1946
Atrypida - Atrypidae	Rugosatrypa nieczlawiensis Rugosatrypa nieczlawiensis
Rhynchonellida -	Rhynchonellida indet. Rhynchonellida indet. Kuhn 1949 globose
Trilobita
-	Trilobita indet. Trilobita indet. Walch 1771 trilobite
Ostracoda
Palaeocopida - Beyrichiidae	Beyrichiidae sp. Beyrichiidae sp. Jones 1894 ostracod