Palaeoenvironment of the Eocene Eckfeld Maar lake (Germany): implications from geochemical analysis of the oil shale sequence

The geochemistry of the oil shale succession points towards a highly productive, eutrophic ecosystem with intense microbial activity under meromictic conditions in the Maar lake. Beside the high input of land plants to the biomass, major contributions from bacteria and phytoplankton are indicated by the biomarker composition.