Late Pleistocene to Middle Holocene record of sedimentation and carbonate content in the Zervynos paleolake-dune complex, Lithuania

Abstract

The Late Pleistocene to the Holocene is a time interval that covers the climate transition from a cold to a warm interglacial regime. In the Baltic region, many studies have focused on estimating environmental responses to climatic forcing using palynological and stratigraphic proxies of glacial and periglacial settings. Herein we describe the mixed lacustrine-aeolian succession of the Zervynos-2 section (south-eastern Lithuania), located in the north-eastern part of the European Sand Belt. The succession and the sedimentation styles were characterized by granulometric parameters, structural features, dolomite/calcite ratio, and paleobotanical macro-remains. Our analyses revealed that the Zervynos-2 paleolake formed on the sandur (outwash) plain during the final stage of the Pleistocene. The onset of lake sedimentation was caused by sudden submergence of a sandbody-constrained paleovalley. Carbonate ratios and macro-remains from the lower gyttja material showed the presence of substantial millennial-scale oscillations, which suggests a delayed response to the isotopically derived paleotemperatures. The transition to the fast sand sedimentation started approximately in the Middle Holocene and is interpreted here as being caused by warming and drying of the climate in the Baltic region. The upper Holocene portion of the section represents the transition to exclusively aeolian sedimentation with lower accumulation rates that are likely related to a long-term cooling trend. The obtained results support the conjecture that there is a direct but delayed positive correlation between dolomite and calcite ratios in lake sediments and the climatic signal in the Greenland GISP2 record.

Keywords

• european sand belt
• sand
• carbonates
• plant macro-remains
• climate events
• bayesian inference.