The Mid-Pleistocene transition in the Eastern Mediterranean: a multi-proxy approach to reconstruct its impact at the southern margin of the Central Anatolian Plateau (CAP)
Sunum, ss.902, 2024
- Yayın Türü: Diğer Yayınlar / Sunum
- Basım Tarihi: 2024
- Sayfa Sayıları: ss.902
- Süleyman Demirel Üniversitesi Adresli: Evet
Özet
The Earth experienced notable influences on both biota and physical environment during the Mid Pleistocene Transition (MPT). The MPT (~1.25 to 0.77 Ma) corresponds to a time of a progressive increase in the amplitude of climate oscillations from a 41-kyr to quasi-100-kyr rhythm, which resulted in increasing long term average global ice volume (Head & Gibbard, 2005). In the Mediterranean region, the MPT is recorded in several offshore successions mainly located in the central and western parts of the basin. However, the eastern part of the Mediterranean has received less attention regarding the MPT. We aim to extend knowledge about the eastern part of the Mediterranean and compare the records of MPT in both on-land and offshore successions. The CAP southern margin hosts Neogene marine sedimentary basins at high elevations (up to 2 km). In the Mut Basin, Middle Pleistocene deposits, reaching up to 1.5 km in elevation, unconformably overlie the Meso Cenozoic succession of the Central Tauride (Öğretmen et al., 2018). We present the preliminary results on a marine succession cropping out in the Mut Basin (~1.1 km a.s.l.) (TOL 1). The studied section is roughly 71 m thick and is predominantly made up of marls, clayey marls, and calcarenite layers, showing a shallowing up trend. We collected samples, with one-meter sampling resolution, for micropaleontological, isotopic and geochemical analyses. Although a strong presence of reworked specimens dilutes the concentration of the in situ species, our preliminary results, based on the calcareous nannofossils biostratigraphy, show two important biostratigraphic events: Gephyrocapsa omega First Occurrence (FO), calibrated at 0.95 Ma (Maiorano et al., 2004), which occurs at the basal part of the sampled section, and Emiliana huxleyi FO, calibrated at 0.26 Ma (Rio et al., 1990), close to the top of TOL 1. Unfortunately, it was not possible to detect the Top common (Tc) of Reticulofenestra asanoi, probably due to interference from reworking. These biostratigraphic events provide a clear hint that the TOL 1 section records the Mid-Pleistocene Transition. Quantitative biostratigraphic investigations on calcareous nannofossils, planktonic and benthic foraminifera assemblages are currently in progress. To define how the climatic changes that occurred during the MPT are recorded in the TOL 1 section, analyses on stable and clumped isotopes, and Mg/Ca ratio on foraminifera shells are still in progress, as well as magnetostratigraphic and calcimetry analyses.