Palaeoecological evolution of Duckmantian wetlands in the Ruhr Basin (western Germany): A palynological and coal petrographical analysis

For this study, six seam sequences of Duckmantian age from the Ruhr Basin, western Germany, were analysed. 155 samples from drill cores were examined, including coal samples, as well as organic-rich and clastic sedimentary rocks. All samples were analysed using palynological and coal petrographical techniques. Based on published information of in situ miospores the encountered dispersed miospores were assigned to their parent plants in order to reconstruct the vegetation history. Six vegetational associations were identified using Detrended Correspondence Analyses (DCA): lepidocarpacean association I, lepidocarpacean association II, lepidocarpacean-sigillarian association, lepidocarpacean-sphenophyll association, lepidocarpacean-fern association, and the subarborescent lycopsid association.Lycospora is the most important constituent in the miospore association as in 75% of all samples the genus is represented with more than 50% relative abundance. Lepidocarpaceans such as Lepidophloios and Lepidodendron are very common among the plant fossils. Hence, arborescent lycopsids dominated the vegetation of the Ruhr Basin during the mid and late Duckmantian, forming flood plains and planar forest mires. Variations in the plant environment are reflected by greater influence of sigillarians, which were typical for swamp margins or for domed swamps, characterized by stunted vegetation. Fern-dominated environments were rare during the Duckmantian.A typical rhythmic succession shows an evolution from clastic flood plains through peat substrate planar mires, followed by a doming of the swamps and formation of ombrogenous mires. Floodplains reappeared during periods of subsidence, accompanied by a rise in water level.