Dayia shirleyi Community, Lowest Noulette Fm., Noulette Borehole, Artois (Silurian of France)

Where: France (50.5° N, 2.5° E: paleocoordinates 24.9° S, 7.9° W)

• coordinate based on political unit

• local area-level geographic resolution

When: Noulette Formation (Lievin Group), Pridoli (423.0 - 419.2 Ma)

• Lowest part of the Lievin Groupo (lowest Noulette Fm. = Calcaire de Lievin sensu Barrois et al. 1922).

• member-level stratigraphic resolution

Environment/lithology: marine; shelly/skeletal, argillaceous limestone and calcareous shale

• 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: "moderately rough water inferred from highly disarticulated nature of most of the specimens...typical low diversity, high dominance unit on a silty bottom...outer BA 2.."

• 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: "Quiet water, argillaceous and shelly limestone. Most of the brachipod specimens are articulated. In some cases shells in calcareous shale and siltstone are disarticulated."

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 26109: 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
Rhynchonellata
 Athyridida - Dayiidae
Dayia shirleyi