Ecology of the Eocene moor landscapes of the Leipzig Embayment

The study of natural climate archives is a significant method to understand past environmental conditions and depositional processes. Investigating Central German lignite is particularly suitable, as it serves as an environmental and climate archive, formed from Tertiary mires and their ecological and climatic conditions.

The petrographic composition of lignite is greatly influenced by the plant communities that formed the paleo-mires, serving as direct indicators of the climate and environmental conditions of that era. These plant communities developed in cyclic sequences, progressing from coniferous swamp forests and angiosperm-dominated peatlands to reed marshes and pine woodlands, culminating in raised bogs.

In this contribution, detailed petrographic and facies analyses of lignite seams are provided to show insights into the physicochemical and ecological conditions of these ancient marsh sequences. Field mapping and core logging at the open-pit mines Profen and Vereinigtes Schleenhain in Central Germany were conducted. Taken samples were analysed macropetrographically, as well as microscopically in terms of maceral analysis and moor facies analysis.

The resulting depositional model reconstructs the development and disturbances of the paleo-mires, revealing external environmental influences. It demonstrates the sequence of moor facies cycles and identifies areas with peat fires or the drying out of the marsh. This includes information on plant communities, groundwater levels, oxygen and nutrient availability, and climatic conditions during deposition. By correlating this information throughout different parts of the Central German lignite basin, new insights into its depositional model are provided.