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The study (MS, diploma thesis) is based on more than 1200 belemnite rostra set from the Lower Cretaceous sediments of locality Štramberk (N Moravia). Investigated rostra come from the collection of Dr. V. Houša, who collected them during the seventies to eighties of the last century, during intensive excavation of the Lower Cretaceous tectonic block named Š-12 "pocket". Belemnite rostra were determined at species and generic levels including 7 species and 18 genera. The majority of belemnite assemblage comes from the Lower Valanginian strata, however, also the Tithonian, Berriasian and Hauterivian taxa are present, what clearly documents the redeposition. The presence of mesohibilitids, known from the Barremian and younger deposits, still remains enigmatic. For better understanding of the redeposition proces, the alveolar infill formed by several generations of sediments, are investigated. Study of these sediments outlines the sedimentary development of the Baška elevation inside the Outer Carpathian system. Preliminary stable isotope data δ18 O and δ13 C received from belemnite rostra show different belemnite life-style during the ontogeny - i.e. juvenile bottom life style and adults inhabiting shallow/warmer waters. Negative values of δ18 O should be correlated with the "Valanginian extinction... |
