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The Permian formations of the South African Karoo Basin play a crucial role in understanding Gondwana's climate history during this time of major global changes. In this paper we present two data sets, one from the coal-bearing Vryheid Formation (Witbank Basin) and one from the Whitehill and Upper Prince Albert formations of the DP 1/78 core (NE Karoo). Our main goal was to study the vegetation changes during this period of global warming and test if the climatic signals could be used to correlate the basinal Ecca group facies with the fluvio-deltaic coal-bearing strata of the Witbank Basin. The palynological record of the No. 2 Coal Seam of the Vryheid Formation indicates a cold climate, fern wetland community, characteristic of lowland alluvial plains, and an upland conifer community in the lower part of the coal seam. Up section, these communities are replaced by a cool-temperate cycad-like lowland vegetation and gymnospermous upland flora. The data set of the DP 1/78 core is interpreted to represent a cool to warm temperate climate represented by a high amount of Gangamopteris and Glossopteris elements. Both data sets are very different in their composition, which can be explained by the differences in depositional environment; however, our findings reveal a different age of the studied assemblages and thus also suggest that both data sets represent different stages in the transition from icehouse to greenhouse during Permian times. As the stratigraphic correlation between the Main Karroo Basin and the peripheral basins is still under discussion, this paper provides new data to underpin the stratigraphic placement of the Whitehill Formation relative to the coal-bearing Vryheid Formation. [ABSTRACT FROM AUTHOR]

This paper presents the results of a palynological investigation of the sands from upper Eocene (Priabonian) epicontinental marine strata at Łukowa, SE Poland. This locality represents an isolated spot of upper Eocene strata in the southern part of epicontinental Poland due to later uplift and erosion of this area. The sands studied yielded a well-preserved palynoflora, providing information about palaeovegetation and palaeoclimate after the Early Eocene Climate Optimum. During the study a total of 94 fossil species of palynomorphs were identified. The results indicate that the vicinity of the sedimentary basin was covered by vegetation with a significant portion of thermophilous taxa and containing many elements with East Asian affinities. The plant communities were composed of Platanus , Platycarya , Engelhardioideae, members of the Hamamelidaceae, Sapotaceae, Fabaceae, Oleaceae, Fagaceae (probably evergreen Quercus and Castanoideae), and Betulaceae families, as well as Salix , Carya , and others. Members of the Pinaceae family and Sciadopitys were components of coniferous or mixed forests. Taxodium , and presumably Glyptostrobus , together with Nyssa , might have covered areas with a higher groundwater level. The pollen of Milfordia and Aglaoreidia cyclops can probably be considered as representing marsh/freshwater vegetation. Cryptogams are represented mainly by ferns (including members of the Lygodiaceae and Schizaeaceae, probably as well as Gleicheniaceae and Cyatheaceae families) and Lycopodiaceae (including Lycopodiella ). The presence of frequent pollen and spores of the genera presently growing under tropical and subtropical climatic conditions and the presence of several taxa characteristic for swamps indicate that the climate during deposition of the sediments studied was warm and humid. The mean annual temperature of 17.2–23.1 °C was estimated on the basis of Coexistence Approach method. [ABSTRACT FROM AUTHOR]

Abstract: In the present paper, we have analyzed thirty-five palynofloras covering the time span from the Early Miocene (Aquitanian) to the Late Miocene (middle Tortonian) in Turkey. The results obtained are presented in tables and maps showing temporal palaeoprecipitation values. The mean annual precipitation (MAP) exceeds 1200mm during the Aquitanian and early-middle Serravallian. It is suggested to have been between 1000 and 1300mm in the latest Serravallian–earliest Tortonian in Western and Central Turkey. In the early-middle Tortonian, the lower boundary of MAP decreases to below 1000mm in Central and Eastern Turkey. Today, MAPs are represented by lower values around 600–1000mm in Western and 400–600mm in Central Turkey. For the driest month (LMP), the rainfall was not distributed homogeneously. In the Aquitanian, the calculations are between 36 and 48mm with humid conditions in Western and Eastern Turkey. During the Burdigalian and Middle Miocene, the driest month precipitation varied with respect to locations. However, it is clear that there was a reduction in precipitation during the early-middle Tortonian, with values around 26–27mm in Central and Eastern Turkey. The same pattern is observed for the wettest month precipitation (HMP), with estimates higher than 200mm during the Aquitanian and earliest Tortonian, although some areas received low rainfall. HMP was reduced between 130 and 140mm in the early-middle Tortonian. The warmest month precipitation (WMP) varied from 96 to 140mm except for Konya–Ilgın, Kırşehir–Hacıbektaş and Manisa–Soma that received 88mm during the Early-Middle Miocene. In the early-middle Tortonian, the amount of summer rainfall lay between 58 and 88mm. The reason of the decrease in all rainfall parameters during the early-middle Tortonian could be related to several factors such as climatic cooling, altitude, aridification, palaeotopograhy or continentality. However, it is necessary to indicate that the Tortonian cooling had previously been proposed by Akgün et al. (2007) as the explanation, using a large number of palynological assemblages in Turkey. We also observe a decrease in precipitation parameters during the Middle Miocene. This could be related to fact that either low species diversity can result in wide coexistence intervals or the Monterey cooling event was related to a cooling during the Langhian and Serravallian. [Copyright &y& Elsevier]

Abstract: This paper presents palynological evidence from the late Early Triassic (late Smithian) to the Late Triassic (Rhaetian) of the Barents Sea area: A continuous palynological succession from an exploration well (7228/7-1A) in the Nordkapp Basin (SW Barents Sea) and palynological data from a series of shallow cores drilled at the Svalis Dome (Central Barents Sea) representing selected Triassic intervals. These fully marine sediments are independently dated by marine faunas. Both records show significant shifts in the distribution of the main floral elements. Changing ratios of spore-pollen taxa, grouped as hygrophytes versus xerophytes and spores versus pollen, reveal major changes of the floras within the studied interval. One distinct turnover coincides with the Smithian/Spathian boundary where lycopsid and pteridophyte spores dominated assemblages change to pollen (pteridosperms and conifers) dominated assemblages. Lower Middle Triassic assemblages are again dominated by lycopsid spores while the assemblages from the upper part of the Middle Triassic and the lower part of the Late Triassic are characterised by dominance of coniferous pollen and show the decline of pteridosperms. In the latest Triassic fern spores are abundant and diverse. In contrast to the Middle Triassic the pollen assemblages are characterized by cycadophytes and Araucariacites. These distribution patterns are interpreted to reflect climatic changes. The presented results from Norwegian Boreal areas confirm the significant differences between quantitative distribution of specific taxa as well as diversity of major groups in plant assemblages from low and mid latitudes. The present survey opens new perspectives for more detailed comparisons and climatic interpretations of floras from the Triassic period, a time during which Mesozoic vegetation established. The major changes in the dominance of specific floral elements, especially the diversification and spreading of the conifers, can probably be related to climatic changes. [Copyright &y& Elsevier]

Terrestrial deposits of the Triassic-Jurassic transition are well developed in the Junggar Basin, located in the Haojiagou Valley of Urumqi, Xinjiang Uygur Autonomous Region of Northwest China. This paper describes the palynology of a 10 m thick lignite bed from the Upper Triassic Haojiagou Formation (Rhaetian) with the aim of reconstructing the palaeovegetation and palaeoenvironment of a peat-forming wetland near the Triassic-Jurassic boundary. The palynoflora contains both Eurasian and Gondwanan elements, and is dominated by the spores and pollen of Bennettitales, Corystospermales, Ginkgoales, and Gleicheniales. At the Triassic/Jurassic boundary (Hettangian), the palynoflora significantly changes as Cyatheales spores become the dominant elements. We analyze assemblages in terms of an Eco-Plant model, which assigns the parent plants of the palynomorphs into five groups based on humidity and four groups based on temperature, and uses multivariate statistical analyses to infer palaeoclimate and palaeoenvironmental conditions. Results suggest that the palaeoclimate of the Rhaetian was generally wet and subtropical with short seasonal drought periods. Our analysis shows that an Eco-Plant model may be a useful tool to reveal past vegetation patterns and climate changes, applicable to other Mesozoic assemblages. • Palynomorph study based on scanning electron microscope and light microscope. • Using Eco-Plant model to reconstruct Mesozoic humidity and temperature. • Palaeoenvironmental reconstruction near the Triassic-Jurassic boundary. • High-resolution Mesozoic palynomorph study • The Upper Triassic terrestrial Haojiagou Formation. [ABSTRACT FROM AUTHOR]