Plant macrofossils from the Czyżów Complex deposits of the Szczerców outcrop, central Poland

Abstract

The paper presents the results of research into the plant macrofossils found in the tectonic Kleszczow Graben, within Mesopleistocene sandy sediments. A number of samples were collected at eight locations from river sediments containing variously sized fragments of plants, mostly from greenish sands overlying Neogene sediments. The structural characteristics of the sediments show a cyclic record of the formation of point bars, their washing out at supercritical conditions, and their aggradation by fine-grained material during flow waning. Based on lithological and structural studies, it has been demonstrated that the sands accumulated in an environment of a meandering river, whose valley bottom was covered with fairly dense vegetation, inhibiting the influx of mineral material to the floodplain from the surroundings – thevalley or glacial plateau slopes. The aim of further analysis was to identify the plant genera of the individual macrofossils (about 40 specimens). The most numerous macrofossils were observed in the middle layers of the profile, within sandy megaripple structures, where mostly fragments of Fraxinus and Acer wood were present. In other layers, several fragments of Pinus and three pieces of Populus wood were identified. Additionally, young stems of dicotyledonous plants and fragments of rhytidome (the outer bark of a tree) were found. The results are discussed in combination with considerations on the deposition of the Czyzow Complex in the Belchatow outcrop, and on the occurrence of local flora.