Middle Miocene peat mire types from the Adamów–Konin Basin in central Poland: lithotype and sedimentological analysis in relation to palynological data

Abstract

The first mid-Polish lignite seam (MPLS-1), mined in the vicinity of Konin and Turek in central Poland, has been subjected to multi-directional studies. These allowed for the deciphering of the environmental conditions in which relatively thick peat deposits were formed in the Middle Miocene. Research into organic matter alone does not allow for a complete determination of the mire type and its evolution. Much valuable additional information on this subject can be provided by a sedimentological study of siliciclastic interbeddings contained within the lignite seam. Therefore, this paper presents the results of low-rank coal lithotypes and clastic facies analysis. MPLS-1 from the Adamów–Konin Basin shows that the use of these two research methods can give satisfactory results. The lithotype analysis showed that sedimentary sub-environments (mire types: fen/open water, bush moor and forest mires, both relatively wet and dry) changed both vertically and laterally. On the other hand, sedimentological analysis of the siliciclastic sediments provides indirect evidence that the Mid-Miocene mires in central Poland existed in the vicinity of river channels. Their waters repeatedly flooded the mires, interrupted their evolution, and significantly increased the ash yield of MPLS-1. Finally, the presented results are in agreement with those obtained from palynological research.