Redefining Eastern Anatolian Tephrochronology: insights from Nemrut and Süphan volcanoes

The Eastern Anatolian Volcanic Province (EAVP) has a highly fragmented and understudied eruption history. The volcanoes of Nemrut and Süphan are known to be major sources of volcanic ash in the eastern Mediterranean region. Numerous distal tephra and cryptotephra layers originating from these two volcanoes are found within important archaeological and palaeoenvironmental records across the region. However, the limited availability of robust glass geochemical data and well-constrained eruption histories has so far prevented these tephra layers being used to their full tephrochronological potential.

Here, we present a refined tephrochronological framework for Nemrut and Süphan, as part of the DFG funded TephroMed and TephroBridge projects. We investigated all the visible tephra layers (V-layers) of the ICDP Ahlat Ridge core, Lake Van (Turkey), focusing on the last Interglacial to glacial period (30-130 ka). The volcanic glasses from these V-layers have been geochemically characterised by using major and minor (EPMA) with the addition of trace element analysis (LA-ICP-MS). This data is combined with glass geochemical analyses of proximal tephra deposits from dated tephra outcrops surrounding Lake Van.

The results reveal the volcanic origins of the 107 V-layers. Integration of this data with new geochemical correlations to dated proximal deposits allows ages to be assigned to key eruption events. This refined tephrochronological framework provides a foundation for investigating interactions between volcanic activity and climatic variability, while significantly improving chronological control of paleoenvironmental and archaeological records. Ultimately, this work enables improved regional synchronisation across the eastern Mediterranean and advances the development of Mediterranean tephrochronology, helping to bridge a critical gap in current knowledge.