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The Silurian-Lower Devonian succession in the Değirmentaş-Halevikdere section (E Taurides) shows considerable lithostratigraphic similarities to the three-partite subdivision, initially documented in the same stratigraphic interval in Saxo-Thuringia and later in other peri-Gondwanan terrains. The Llandovery-Wenlockian part of the studied section (ca. 40 m) is characterized by black graptolitic shales. The Llandoverian part is dominated by radiolarian ribbon cherts (ca. 20 m). The Rhuddanian Akidograptus ascensus, Parakidograptus acuminatus, and Cystograptus vesiculosus biozones have been recognized in its lower part, while in the upper part of the succession, the lowermost Telychian Rastrites linnaei Biozone has been documented. The Telychian Spirograptus turriculatus and Streptograptus crispus biozones, as well as the Sheinwoodian Cyrtograptus rigidus/Monograptus belophorus Biozone, have been identified within this succession. Graptolites of the Homerian (Colonograptus deubeli + Col. praedeubeli and Col. ludensis biozones) are only found in the Pekmezkoy and Gurleşen areas, in the black shales, immediately before the first ocher-colored limestone, which is characteristic for the Ockerkalk Formation in the Thuringian facies. The dominantly ocher-colored shale-limestone alternation in the Değirmentaş-Halevikdere section is ca. 50 m in thickness. The lower Ludlowian part is enriched by nautiloids, while in the Pridolian part crinoids are abundant. It is covered by 60-m-thick black shales and siltstones, corresponding to the Upper Graptolite Shale Formation in the Thuringian. The Silurian-Devonian boundary is located in the lower part of this unit on the basis of lobolith findings. The depositional model proposed here accounts for the migration of the considered peri-Gondwana terrains from high to low paleogeographic latitudes that has triggered changes not only in the ocean water thermohaline circulation but also in the wind-driven downwelling or upwelling systems. These changes are responsible for the progressive transition from an oxic regime to an anoxic one in the deep oceanic depositional environments (outer continental shelf, slope, and ocean basin settings) and the deposition of light and dark sediments there. [ABSTRACT FROM AUTHOR]

The studied Gülüç section of the Silurian Fındıklı Formation is situated on the western bank of Gülüç Creek in Ereğli, NW Anatolia, Turkey, in the eastern part of the Zonguldak Terrane. The Gülüç section consists of 3 sedimentary packages: greenish grey limy siltstones, 5-7 m thick (1), overlain by an irregular alternation of black shales and clayey limestones, about 15 m thick (2), and a 6-7 m thick succession of mainly siltstones and sandy limestones (3). A combined biostratigraphy based upon graptolites, cryptospores and conodonts indicates that Package 1 is of Llandovery (Rhuddanian, Aeronian and/or early Telychian) age, Package 2 and Package 3 are of late Wenlock--early Ludlow (Homerian and Ludfordian) age. Graptolites in packages 2 and 3 indicate the presence of the Cyrtograptus lundgreni, Neodiversograptus nilssoni and Lobograptus scanicus graptolite biozones. The Ozarkodina crassa Biozone occurs in the lower Gorstian (Ludlow). The specific features of the Gülüç section (lithological changes, condensation, stratigraphic gap, change in graptolite diversity) are related to the global model of Silurian T--R cycles. The Silurian Fındıklı Formation in the Gülüç section, about 20 m thick, represents a condensed lithological succession which differs significantly from the coeval thick, stratigraphically widespread black shales and siltstones of the same formation in the Zonguldak and İstanbul terranes. Sixteen cryptospore species are described and their stratigraphic and geographic distributions are summarised. [ABSTRACT FROM AUTHOR]