One hundred and nine taxa of carpological remains, 3 taxa of leaves, and 103 taxa of sporomorphs are identified from the late Oligocene to Early Miocene deposits at the Tetta Clay Pit, eastern Germany. Palynological analysis was performed for the first time for this site. Among the carpological remains, 82 taxa are documented for the first time for this site, including two new fossil-genera (Paranothotsuga Kowalski gen. nov., Pterosinojackia Kowalski gen. nov.), and one new fossil-species (Sparganium tuberculatum Kowalski sp. nov.). New combinations are also introduced (Paranothotsuga jechorekiae (Czaja) Kowalski n. comb., Magnolia germanica (Mai) Kowalski n. comb., and Morella stoppii (Kirchheimer) Kowalski n. comb.). Discovered microremains of Pesavis tagluensis fungus extend the age range of the sedimentary sequence from the previously suggested Middle Miocene to at least the latest Oligocene. Two biostratigraphic units, the Rott-Thierbach and Wiesa-Eichelskopf floristic complexes are recognized for the first time in Tetta. Beech forests are indicated as the most common vegetation type. All of these fossil assemblages evidence a warm temperate climate, but a shift toward a warmer subtropical climate is inferred in the uppermost part of the studied profile.
The Bełchatów lignite deposits are a rich archive allowing palaeoenvironmental, palaeoecological and palaeoclimatic reconstructions from the Neogene and Quaternary periods. We describe the results of palynological studies (including non-pollen palynomorphs) of eight samples from the lower Miocene KRAM-P 211/214 collection of plant macroremains. The results of this palynological analysis are consistent with the results of previous studies of plant macroremains and significantly enrich our knowledge of vegetation and palaeoenvironment. Both studies indicate the presence of a freshwater body (a moderately large and deep lake) surrounded by wetland vegetation (including swamp forests with Glyptostrobus, Taxodium, Nyssa and Osmunda) and upland mesophytic forests. Evergreen or at least semi-evergreen forest communities grew along the ancient shores of the lake and on the slopes of the Mesozoic calcareus rocks surrounding the lake. In the lake, green algae (Pediastrum, Tetraedron and some Botryococcus) and freshwater peridinoid dinoflagellates were major components of the algal community. The same lake was the source of previously identified animal remains: freshwater fishes, molluscs, and mammals, including Megachiroptera bats. Our analysis shows that the climate was subtropical and humid, with an estimated mean annual temperature of 16.8–17.8°C.
Palynological analysis of the 1st mid-Polish lignite seam (MPLS-1) of the Drzewce deposit (Konin region, central Poland) was used as the data source for palaeoenvironmental and palaeoclimatic interpretations. Lignites of the 1st group developed in the middle Miocene, during and shortly after the last peak of the Mid-Miocene Climatic Optimum, over a large area of Poland, and they are the youngest of the main Neogene lignite seams in Poland. In the Konin region, these lignites have a relatively significant thickness (up to 20 m) and therefore they are (or were in the past) exploited in several open-pit mines. A total of 36 palynological samples from the 6.3-m-thick seam of the Drzewce opencast mine was studied in detail. Palynological analysis of the lignite seam indicates that the area was overgrown by palustrine wetland communities, similar in composition to modern pocosins. The most characteristic elements of them were shrubs in the Ericaceae family. The climate at that time was warm temperate and humid. The estimated mean annual temperature (MAT) for the lignite seam at Drzewce is 15.7–17.8 °C. Comparison with other palynofloras from the MPLS-1 shows that the climate during the formation of the group of seams was more or less homogenous across the entire Polish Lowlands. Sedimentological data and results of palynological studies (including NPPs) at Drzewce indicate that the palaeomires were relatively distant from the channels of the river system in the Konin Basin. The fossil fungal assemblage indicates dense vegetation on damp, swampy soils and the presence of small, shallow-water bodies, with a variable water level or even periodic reservoirs, existing only during the wet season or after floods. In small, flooded depressions, such as the pools in bogs, filamentous green algae occurred. The presence of zygospores of the desmids Desmidiaceaesporites cosmarioformis most probably indicates relatively nutrient-poor (ombrotrophic) conditions. Fluctuations in the frequency of individual plant taxa (including Sequoia and Sciadopitys) are likely to reflect changes in water level and trophic conditions.
Many geological problems have not been convincingly explained so far and are debatable, for instance the origin and changes of the Neogene depositional environments in central Poland. Therefore, these changes have been reconstructed in terms of global to local tectonic and climatic fluctuations. The examined Neogene deposits are divided into a sub-lignite unit (Koźmin Formation), a lignite-bearing unit (Grey Clays Member), and a supra-lignite unit (Wielkopolska Member). The two lithostratigraphic members constitute the Poznań Formation. The results of facies analysis show that the Koźmin Formation was deposited by relatively high-gradient and well-drained braided rivers. Most likely, they encompassed widespread alluvial plains. In the case of the Grey Clays Member, the type of river in close proximity to which the mid-Miocene low-lying mires existed and then were transformed into the first Mid-Miocene Lignite Seam (MPLS-1), has not been resolved. The obtained results confirm the formation of the Wielkopolska Member by low-gradient, but mostly well-drained anastomosing or anastomosing-to-meandering rivers. The depositional evolution of the examined successions depended on tectonic and climatic changes that may be closely related to the mid-Miocene great tectonic remodelling of the Alpine-Carpathian orogen. This resulted in palaeogeographic changes in its foreland in the form of limiting the flow of wet air and water masses from the south and vertical tectonic movements.
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