Systematics and biostratigraphy of Oligocene (Rupelian-Early Chattian) foraminifera from lagoonal-very shallow water limestone in the eastern Sivas Basin (central Turkey)

Oligocene (Rupelian-early Chattian) new larger benthic foraminiferal taxons such as miliolid genus Sivasina n. gen., SİREL & ÖZGEN-ERDEM (type species Sivasina egribucakensis n. gen. n. sp. SİREL & ÖZGEN-ERDEM) occurs in the Eğribucak, Bakımlı, Tuzlagözü and Çaygören sections (E of Sivas). One new Rupelian-early Chattian lagoonal-shallowest-water peneroplid species Peneroplis flabelliformis n. sp., SİREL & ÖZGEN-ERDEM from the Eğribucak, Tuzlagözü and Çaygören sections and Rupelian lagoonal two new peneroplid species Coscinospira sivasensis n. sp. SİREL & ÖZGEN-ERDEM, Coscinospira elongata n. sp. SİREL & ÖZGEN-ERDEM from the Eğribucak section (E of Sivas), two new Rupelian shallowest-water alveolinid species Praebullalveolina oligocenica n. sp. SİREL & ÖZGEN-ERDEM and Praebullalveolina minuta n. sp. SİREL & ÖZGEN-ERDEM from the Bakımlı section are described and figured. Furthermore, the description of the known Oligocene soritid species Praearchaias diyarbakirensis SİREL, Praearchaias minimus SİREL, Archaias kirkukensis HENSON, Archaias asmaricus SMOUT & EAMES, peneroplid species P. cf. laevigatus d’ ORBIGNY and austrotrillinid species Austrotrillina brunni MARIE are given shortly. In addition, the biostratigraphy of four studied sections are introduced. </span

Palaeontological evidence and sedimentary facies in a lower Miocene (Aquitanian) succession from the Bingol minibasin (Sivas Basin), Central Anatolia

WOS: 000445963200001The results of palaeontological (palynological and mollusc) and sedimentological analyses of the lower Miocene deposits from the Bingol minibasin, a part of the Sivas Basin, are exhibited to define the vertical shifts in sedimentation environments and plant covers, linking to eustasy. The presence of index species Corbulomya (Lentidium) aquitanica suggests an Aquitanian age for the studied succession, which can be divided into three informal units: a lower unit, a middle unit, and an upper unit. Fine-grained sediments of the lower unit were deposited in a low sea-level setting due to high quantities of terrestrial palynomorphs. This unit is overlain by the middle unit, coralgal limestone, which marks the first initiation of Aquitanian transgression. Continuing shallow marine settings in the upper unit gave rise to deposition of coarse to fine-grained sediments. Palynological data were recovered from the fine-grained sediments of the lower and upper units. A total of 35 spore and pollen taxa were recorded, including 2 spores from ferns, 5 gymnosperms, 26 angiosperms, 1 group of undifferentiated dinoflagellate cysts, and 1 fresh water alga of Botryococcus sp. The pollen spectrum is dominated by coniferous forest, mainly undifferentiated Pinaceae, and herbaceous communities including high quantities of Poaceae and Chenopodiaceae-Amaranthaceae, with minor contributions of Ephedra sp., Caryophyllaceae, and Asteraceae subf. Asteroidae. High sea-level conditions, which started with sedimentation of the middle unit, survived during the deposition of the upper unit due to being overwhelmingly dominated by dinocysts. Thermophile plants including Avicennia sp., Engelhardia sp., Myrica sp., Sapotaceae, Cyrillaceae-Clethraceae, and Reveesia sp. along with relatively high quantities of xerophytes and the quantitative palaeoclimate values imply a subtropical and dry palaeoclimate.Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [109Y041]This study was supported by a research grant from the Scientific and Technological Research Council of Turkey (TUBITAK Grant No. 109Y041). The assistance provided by Mehmet Can Diyarbakirli, who took part in the fieldwork, is acknowledged. The authors would like to thank Ali Gurel, two anonymous reviewers, and the manuscript editor, Aysegul Yildiz, for their helpful comments