Magnetostratigraphy of the Pikermian fauna-bearing late Miocene central Anatolian Sivas Basin (Turkey)
Authors: Meijers Maud J.M. , Kaya Ferhat , Peynircioglu Ahmet , Bibi Faysal , Pehlevan Cesur , Mulch Andreas , Langereis Cor G. 
Published: March 2022

&lt;p&gt;The Pikermian chronofauna is associated with C&lt;sub&gt;4&lt;/sub&gt; vegetation and the potential hominin &lt;em&gt;Graecopithecus freybergi &lt;/em&gt;in Greece and Bulgaria and forms part of the Old World Savannah Paleobiome. This study provides a new magnetostratigraphy for thestratigraphic interval that includes the Haliminhan&amp;#305; and Hayranl&amp;#305; mammal sites from the central Anatolian Sivas Basin (Turkey), which show high faunal similarities to the Pikermian chronofauna.&lt;/p&gt;&lt;p&gt;Dated sites harboring Pikermian fauna in Turkey, Greece, and Bulgaria range in age between 11 and 7.3 Ma. Based on biostratigraphy, the Haliminhan&amp;#305; and Hayranl&amp;#305; fossil horizons were previously placed within European Mammal Neogene (MN) zones MN11-MN12 (ca. 9 to 7 Ma). A new magnetostratigraphy in 140 m thick continental deposits refines the age estimate to 8.0&amp;#8211;6.5 Ma for the fossil mammal-bearing levels of the Sivas Basin.&lt;/p&gt;&lt;p&gt;Negative covariance between &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C and &amp;#948;&lt;sup&gt;18&lt;/sup&gt;O values of bulk carbonate from the fluvio-lacustrine beds indicates an open lake hydrology; &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C and &amp;#948;&lt;sup&gt;18&lt;/sup&gt;O values suggest a positive water balance and no significant long-term changes in hydrology and primary productivity within the lake that once covered the Sivas Basin. Two intervals of increased &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C (by ca. 6&amp;#8211;8&amp;#8240;) within the section are followed by a similar decrease over total time intervals of ca. 150 kyr. An increase of biogenic productivity can increase &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C in lacustrine carbonate and may either result from changes in nutrient input or temperature. The absence of simultaneous changes in &amp;#948;&lt;sup&gt;18&lt;/sup&gt;O during peaks in &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C make temperature an unlikely driver and we therefore conclude that nutrient input adjustments to the basin were responsible for the two peaks in &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C.&lt;/p&gt;&lt;p&gt;Our results suggest that the Pikermian chronofauna of the Sivas Basin thrived under relatively stable local hydrological and climatic conditions. In the Sivas Basin, the Pikermian fauna flourished well into the Messinian, as opposed to Greek and Bulgarian sites where faunal turnover was observed under a cooling climate and mid-latitude desertification across the Tortonian-Messinian boundary.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Key words &lt;/strong&gt;magnetostratigraphy, stable isotope geochemistry, mammal stratigraphy, late Miocene, Pikermian, central Anatolia&lt;/p&gt;&lt;p&gt;&lt;strong&gt;References &lt;/strong&gt;B&amp;#246;hme et al. (2017). PLoS ONE, https://doi.org/10.1371/journal.pone.0177347;&amp;#160;B&amp;#246;hme et al. (2018). Global and Planetary Change, https://doi.org/10.1016/j.gloplacha.2018.07.019 ;&amp;#160;Meijers et al. (2018). Earth and Planetary Science Letters, https://doi.org/10.1016/j.epsl.2018.05.040;&amp;#160;Meijers et al. (2020). Geosphere, https://doi.org/10.1130/GES02135.1;&amp;#160;Meijers et al. (2022). Newsletters on Stratigraphy, https://doi.org/10.1127/nos/2021/0623&lt;/p&gt;