Jurassic/Cretaceous Carbonate Platforms

Research project P 14707 Jurassic/Cretaceous Carbonate Platforms Alois FENNINGER 27.11.2000 Upper Jurassic to Lower Cretaceous Palaeoecology, Facies Patterns and Carbonate Platform Dynamics: Isolated Platforms and Epicontinental Shelfs Compared The Upper Jurassic to Lower Cretaceous time was a period of significant carbonate platform and reefal development in Europe. Tectonic events and the high sea-level stand led to the formation of two particular shallow-water regions, which are of importance for the proposed project: the southern margin of the Bohemian Massif as a part of the epicontinental European Plate, on the one hand, and the Northern Calcareous Alps (NCA), on the other. Both areas were separated by an oceanic basin. While carbonate platforms of the epicontinental shelf are represented by ramp structures with coral reefs, siliceous sponge reefs, and microbialite reefs, shallow-water environments of the NCA are characterized by steeply bordered, "Bahama-type", isolated platforms, which lack sponge reefs and microbialite reefs. The proposed project aims to study the development of Upper Jurassic to Lower Cretaceous carbonate platforms of the two different settings. Main topics will be the distribution of facies patterns, platform dynamics, and the palaeoecology of reefs. We will compare the epicontinental setting in Austria, which shows a more or less continuous development during the Malm, with platforms of the NCA, which were newly formed within an oceanic setting during late Oxfordian/ Kimmeridgian time. The major scientific innovation of this project will be the designation of carbonate platform- and reef-models in the proposed areas, as well as the evaluation of existing models for the epicontinental Tethys. Especially in the NCA, where present knowledge on this topic is particularly poor, the project will provide new insights into the environmental and sedimentological processes in Mesozoic shallow-water areas and will complete the understanding of Late Jurassic/Lower Cretaceous carbonate systems.