Mid-Holocene Climate Record in Santovka Travertine (Slovakia) and regional Biases of Climate Shifts 8.2 and 7.4 ka BP

Abstract. The study of freshwater carbonates, such as travertines and speleothems, provides valuable insights into the regional biases of mid-Holocene climate development in Central-Eastern (CE) and South-Eastern (SE) Europe. The formation of a lake in the travertine deposition system of the Santovka site, located at the transition of the Western Carpathians and the Pannonian Basin, has led to the preservation of a valuable record. We analyzed the litho- and microstratigraphy, chemical composition, including δ18O and δ13C stable isotopes, and geochronology of the Santovka-village section. We then compared these palaeoclimatic records with reference records from Central-Eastern and South-Eastern Europe in terms of significant climate shifts. The prevalent part of the section studied, which spans between 8200 and 6400 cal BP, is represented by fluvial/fluvio-lacustrine sediments and lake marl. The 8.2 ka BP event was only detected in the δ13C record from the nearby Santovka-PB section. However, we found an abrupt change in both isotopic records around 7400–7200 cal BP, which is likely connected to increased detrital input and some minor palaeoecological changes in the Santovka-village section. These changes are most likely associated with the drying of the lake. The 8.2 event in Central-Eastern (CE) and South-Eastern (SE) Europe is well reflected in the δ13C records, while the change in δ18O was insignificant. In contrast, the newly suggested climate shift around 7400–7000 ka BP was detected at most sites in both δ18O and δ13C records. This development could be connected to a change in air mass circulation, synchronous with declining solar irradiance and increased evidence of drift ice in the North Atlantic.