TY - JOUR A1 - Teschner,C. A1 - Reichenbacher,B. T1 - Otolith-based age determination of mid-Burdigalian marine sediments in the North Alpine Foreland Basin JF - Bulletin of Geosciences JA - Bull. Geosci. Y1 - 2017 VL - 92 IS - 2 SP - 143 EP - 152 CY - Prague PB - Czech Geological Survey SN - 1803-1943 (online), 1802-6222 (print) AV - Free KW - Sr isotopes KW - fossil otoliths KW - biostratigraphy KW - chronostratigraphy KW - chemostratigraphy KW - Central Paratethys KW - Upper Marine Molasse AB - Precise age constraints are rare for the Oligocene to Miocene sediments in the North Alpine Foreland Basin, also referred to as Molasse Basin. This is mainly due to the lack of index fossils, absence of continuous outcrops and scarcity of radiometrically datable rocks. In this study, we applied the Sr isotope dating technique to fossil teleost fish otoliths to determine absolute ages for Lower Miocene (mid-Burdigalian, lower Ottnangian) marine sediments. The fossil otoliths from the marine genera Diaphus and Coelorinchus used in our analysis were recovered from the Neuhofen Beds in the SE German Molasse Basin. For the first time, leaching experiments were conducted on different otolith fractions to extract the ambient 87Sr/86Sr seawater signal. Based on the latest version of the evolution curve for the 87Sr/86Sr ratio in the global ocean, our new data suggest an age of 17.1 ± 0.3 Ma, which is at least 0.6 m.y. younger than hitherto assumed for the Neuhofen Beds based on biostratigraphy and lithostratigraphic correlations. We suggest that strong riverine inputs could account for this shift in the Sr isotope signal to younger ages. ER -