Hastarian/Ivorian (Tournaisian) boundary based on conodont biostratigraphy in the eastern Taurides, Turkey

摘要

Tournaisian successions in Taurides (Turkey) maintain uniform lithologies, particularly alternations of limestone and shale. In the light of bioevents of biostratigraphically significant species in the section, two zones have been established across the Tournaisian succession in the eastern Taurides: the Polygnathus inornatus Zone (Hastarian-Lower Tournaisian) and the Gnathodus cuneiformis-Polygnathus communis communis Zone (Ivorian-Upper Tournaisian). Based on conodont assemblages, the Hastarian-lvorian boundary has been delineated by the first occurrence of Gnathodus cuneiformis, an index taxon for the basal part of the Ivorian. (C) 2015 Elsevier Ltd. All rights reserved.