DEVONIAN SEQUENCES OF THE CENTRAL AND EASTERN TAURIDES (TURKEY) – BIOSTRATIGRAPHY, FACIES, AND GLOBAL EVENTS

Key Devonian sections of the Central and Eastern Taurides have been studied in a Turkish-German cooperation project (DEVEC-TR) with respect to biostratigraphy, sedimentology, facies development, and global events (Wehrmann et al., 2010). Each of the sections is several hundred meters in thickness. Paleogeographically, they were situated at the northern margin of the Gondwana Supercontinent/Peri-Gondwana. The sequences record a spectrum of different environmental conditions ranging from coastal to marine shelf settings. Some of the particular facies are unusual for the respective time intervals compared to other regions. Although the details in facies development differ from one section to another, general trends of changing environmental regimes are visible: The lower parts are dominated by siliciclastics, followed by carbonate-dominated middle parts, and mixed siliciclastic-carbonate deposits in the upper portions. At several levels, global events can be recognized (e.g., Frasne Event, Lower Kellwasser Event). When compared with areas located at the southern margin of Laurasia, the paleobiogeographic distribution of various fossil organisms (fauna as well as flora) indicates only a comparatively narrow seaway (Rheic Ocean) between Laurasia and Gondwana/Peri-Gondwana during the Devonian. New biostratigraphic work, utilizing different groups of fossil organisms, now permits much more detailed age assignments of these sequences than known formerly.