ammonites
Gracianella graciosa Community, Prague Basin (Silurian of Czech Republic)

Where: Czech Republic (49.5° N, 13.5° E: paleocoordinates 47.7° S, 53.7° E)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Monograptus ultimus zone, Pozary Formation, Pridoli (418.7 - 416.0 Ma)

• Pozary Fm. also known as Pridoli Fm.

• formation-level stratigraphic resolution

Environment/lithology: marine; calcareous lime mudstone and shale

• General for Pridoli: "The beginning of the Pridoli was marked by a deepening...[shallow Lsts succeeded by micritic Lsts and calc. shales]...Horny discerned two basic lithofacies in the Pridoli Fm., namely the 'marly' lithofacies formed by rhythmic sedimentation of dark micritic limestone alternating with dark calcareous shales, and the 'carbonate' lithofacies of highly fossiliferous, biosparitic Lsts. The boundary between the two units...is not sharp...Due to a gradual shallowing towards the top of the Pridoli, the area of carbonate sedimentation expanded in the upper part of the Pridoli Formation...and persisted into the lowermost Lochkovian..." [carbonate lithofacies overlies marly]

•

•For this Community: "The presence of abundant graptolites with the shelly benthos suggests a BA 3-4 assignment."

• "marly facies" "...graptolites...occur on bedding planes with shelly fauna..."

Primary reference: V. Havlicek and P. Storch. 1999. Silurian and Lochkovian communities in the Prague basin (Barrandian area, Czech Republic). in A. J. Boucot and J. D. Lawson, eds. Paleocommunities--a case study from the Silurian and Lower Devonian. Cambridge University Press, Cambrdige. 200-228 [M. Foote/M. Foote/M. Foote] more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 14113: authorized by Michael Foote, entered by Michael Foote on 15.05.2002