Givetian
Préat, A.; Bultynck, P.; Brice, D. (2006). Givetian. Geol. Belg. 9(1-2): 9-18 In: Geologica Belgica. Geologica Belgica: Brussels . ISSN 1374-8505; e-ISSN 2034-1954, more |   |
| Keywords | Geological time > Phanerozoic > Paleozoic > Palaeozoic > Devonian > Devonian, Middle > Givetian
Brachiopoda [WoRMS]; Conodonta; Ostracoda [WoRMS]; Rugosa † [WoRMS]
Belgium, Vresse-sur-Semois [Marine Regions]
Marine/Coastal | | Author keywords | Givetian, lagoons, tidal flats, patch reefs, coralgal banks, carbonate platform |
| Abstract | The Givetian Stage in the Givet area is represented by the main part of the Hanonet Fm, the Trois-Fontaines Fm, the Terres d'Haurs Fm, the Mont d'Haurs Fm, the Fromelennes Fm and the lowest part of the Nismes Fm. During Eifelian-Givetian transition, the sedimentary systems evolved from a mixed siliciclastic-carbonate ramp to a carbonate platform dominated by cyclic tidal-flat and lagoonal wackestones with local patch reefs or coralgal banks. The shelf had an ESE-WNW trend and extended from the Avesnois basin (northern France) in the west to Aachen (western Germany). The sedimentation in the Ardennes consists of shallow water regressive metric (around 5 m or less) cycles. Stromatopores, corals, brachiopods, algae and cyanobacteria are abundant. Due to this general shallow water setting, the base of the Givetian Stage has been defined by the IUGS Subcommission on Devonian Stratigraphy in a GSSP in southern Morocco referring to the first occurence of the condodont species Polygnathus hemiansatus. The conodont species Icriodus obliquimarginatus appears approximately at the same level in Belgium. |
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