Sediments of thirty-one short cores from a small lake in NE Poland were studied to better understand the elemental response of the deposits in relation to changing water column conditions. We found that iron (Fe) and manganese (Mn) burial is controlled by geochemical focusing – a tendency of elements to concentrate in a given spot – and that sediment lithology is intrinsically connected to prevailing oxygen conditions. This sheds new light on indicators of past water oxygenation.

Sediment cores from the volcanic lake Holzmaar provide a very precise chronology based on tree-ring-like annual laminations or varves. We statistically combine this varve chronology with radiometric dating and tested three different methods to upgrade the age–depth model. However, only one of the three methods tested improved the dating accuracy considerably. With this work, an overview of different age integration methods is discussed and made available for increased future demands.

High-resolution geochemical imaging techniques provide new opportunities to investigate the biogeochemical composition of sediments at micrometer scale. Here, we compare biogeochemical data from biochemical varves with meteorological data to understand how seasonal meteorological variations are recorded in varve composition. We find that these scanning techniques help to clarify climate–proxy relationships in biochemical varves and show great potential for high-resolution climate reconstruction.