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Soliman A.,University of Graz | Soliman A.,Tanta University | Feist-Burkhardt S.,SFB Geological Consulting and Services | Harzhauser M.,Natural History Museum Vienna | And 2 more authors.
Palynology | Year: 2013

The organic-walled dinoflagellate cyst Mendicodinium mataschenensis is introduced here as a new species. The taxon derives from lower Tortonian clays from the Mataschen clay pit in Styria, Austria. These deposits formed in Lake Pannon, which was characterized throughout the Late Miocene by its highly endemic and rapidly evolving biota. As most species of Mendicodinium are known from restricted marine and brackish paleoenvironments, its occurrence in Lake Pannon may be considered further evidence for the brackish water conditions prevailing in this lake. © 2013 Copyright Taylor and Francis Group, LLC. Source

Riding J.B.,British Geological Survey | Leng M.J.,University of Leicester | Leng M.J.,British Geological Survey | Kender S.,British Geological Survey | And 2 more authors.
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2013

The Early Jurassic Epoch was a predominantly greenhouse phase of Earth history, but a comprehensive understanding of its climate dynamics is hampered by a lack of high resolution multi-proxy environmental records. Here we report a geologically brief (approximately several hundred thousand years) negative carbon isotope excursion (CIE) of 2-3‰ in both marine and terrestrial materials, recognised for the first time for the Late Sinemurian Substage (Early Jurassic, ~. 194. Ma) of eastern England. The Late Sinemurian carbon isotope excursion, which is termed the S-CIE herein, is accompanied by peaks in the abundance of the pollen grain Classopollis classoides and the dinoflagellate cyst Liasidium variabile. Classopollis classoides was thermophilic and is a reliable proxy for hot/warm climatic conditions. Liasidium variabile is interpreted as thermophilic and eutrophic using multivariate statistics, its fluorescence properties being similar to living heterotrophic dinoflagellate cysts, and its association with C. classoides. Moreover, the morphological and ecological similarities of L. variabile to the Cenozoic genus Apectodinium are noteworthy. The co-occurrence of the acmes of C. classoides and L. variabile with a negative CIE is interpreted here as having wide geographical significance due to the marine and terrestrial carbon isotope signals being precisely in phase within an open marine setting. This is consistent with an oceanic-atmospheric injection of isotopically-light carbon, coupled with global warming and increased marginal marine nutrient supply, possibly the result of increased precipitation due to an enhanced hydrological cycle or a seasonally-stratified water column. A probable sea level rise of at least regional extent has been identified at the L. variabile event in other records, which supports this putative phase of global warming. All these features are common to the Paleocene/Eocene thermal maximum (PETM, ~. 56. Ma), and there are also similarities with the Early Toarcian oceanic anoxic event (T-OAE, ~. 182. Ma). © 2012 Natural Environment Research Council. Source

Gotz A.E.,Rhodes University | Feist-Burkhardt S.,SFB Geological Consulting and Services
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2012

Anisian (Lower Muschelkalk) phytoplankton associations of the NW Tethys shelf and the northern Peri-Tethys Basin are characterized by acritarchs and prasinophytes. Stratigraphical and lateral variations in the distribution pattern of these phytoplankton groups were analyzed in key sections of the central basin (Germany), the southern gate areas (Switzerland, Poland) and the northwestern Tethys shelf (Hungary) with the aim to infer palaeoenvironmental changes related to the basin evolution. Stratigraphically, maximum abundance of marine phytoplankton is recognized during phases of maximum flooding. Laterally, a dominance of different phytoplankton groups within these intervals is documented. In the central part of the basin, prasinophytes reach 80% percent of the total plankton association. Sediments of the basin margin, the gate areas and proximal shelf show high amounts of acritarchs ranging from 76% to 95%. These signatures clearly reflect the basin evolution of the Anisian (Lower Muschelkalk) Peri-Tethys Basin and the interaction between a restricted, intracratonic basin and an open ocean. Generally, the Peri-Tethys Basin is characterized by a stratified water column with oxygen depleted bottom waters and maximum abundance of prasinophytes. During phases of transgression, cooler waters from the shelf flood the restricted basin, displayed in the acritarch dominated phytoplankton associations of the shelf and gate areas. Marginal parts of the basin are generally well oxygenated and dominated by acritarchs. Within the acritarch assemblage Veryhachium spp. is characteristic of the marginal and central parts of the basin, whereas Micrhystridium spp. dominates shelf deposits and sediments of the gate areas, respectively. The present study highlights the significance of different phytoplankton associations in basin analysis and high-resolution sequence stratigraphy. © 2012 Elsevier B.V. Source

Riding J.B.,British Geological Survey | Pound M.J.,Northumbria University | Hill T.C.B.,Natural History Museum in London | Stukins S.,Natural History Museum in London | Feist-Burkhardt S.,SFB Geological Consulting and Services
Palynology | Year: 2012

The John Williams Index of Palaeopalynology (JWIP) is the result of the lifetime's work of Dr John E. Williams. Housed at the Department of Palaeontology of The Natural History Museum (NHM) in London, the JWIP is publically available and provides probably the most comprehensive fully cross-referenced catalogue on palaeopalynology in the world. It has 23,350 references to fossil palynomorph genera or species as of February 2012. Since its inception in 1971, every publication in the collection referring to a fossil palynomorph genus or species has been critiqued by John E. Williams. Each item is given an accession number and appropriately referenced within the JWIP using index cards which are sorted alphabetically. Once added to the main reference subindex, further entries are completed for four themed subindexes. The first three of these are sets of cards on the three major palynomorph groups (acritarchs/dinoflagellate cysts, chitinozoa and pollen/spores), 26 stratigraphical intervals and 17 geographical areas. The fourth themed subindex is where each palynomorph taxon has a card (or cards) listing all the records of that species in the literature within six categories (acritarchs, dinoflagellate cysts, chitinozoa, fungal spores, pollen/spores and miscellaneous). Due to the sustained and meticulous recording of data since 1971, users can therefore search the database by major palynomorph group, species, age and/or geographical region. The comprehensive and cross-referenced nature of the JWIP means that researchers can readily identify key publications on, for example, specific palynomorph types over a particular interval in a prescribed area. The JWIP is currently entirely analogue, but the NHM is currently evaluating potential strategies for digitisation. © 2012 AASP - The Palynological Society. Source

Horikx M.,Leibniz University of Hanover | Hochuli P.A.,University of Zurich | Feist-Burkhardt S.,SFB Geological Consulting and Services | Heimhofer U.,Leibniz University of Hanover
Review of Palaeobotany and Palynology | Year: 2016

The evolution of angiosperms significantly changed the composition of the terrestrial vegetation during the mid-Cretaceous. In contrast to the wealth of information available on the biology and systematic relationships of early angiosperms, the temporal patterns of their evolution and radiation are poorly constrained. Here we present a continuous angiosperm pollen record from well-dated shallow marine deposits in the Lusitanian Basin, Portugal. The São Julião section provides a solid stratigraphic framework to track angiosperm pollen distribution patterns from the early Albian to early Cenomanian at mid-latitudes. In comparison to previous angiosperm pollen records from the Lusitanian basin, the section shows an extended late Albian succession and provides new insights into the diversification of early angiosperms during this important interval. Productive palynological samples were analysed and 79 different angiosperm pollen types have been recorded. Throughout the Albian angiosperm pollen represent only a minor component of the total palynoflora. The early Albian pollen record is characterized by highly diverse assemblages of monoaperturate pollen of monocot or "magnoliid" affinity and by the first appearance of polyporate and tricolpate pollen of eudicot affinity. A distinct diversification phase among tri- and poly-aperturate pollen (e.g., Cretacaeiporites, Retitrescolpites, Rousea, Striatopollis and Tricolpites) and the presence of conspicuous pollen grains assigned to Dichastopollenites characterize the middle and late Albian palynological assemblages. Thus, the section records a striking sequence of appearances of important angiosperm pollen morphologies. Monocolpates, polyporates and tricolpates appear in the early Albian whereas tricolporates appear from the early part of the late Albian onwards. Furthermore, well-constrained biostratigraphic ranges of selected angiosperm pollen from mid-latitudes are presented. In view of these new data, the temporal framework of the palynological Subzones II-B and II-C in the Potomac Group succession from the Atlantic Coastal Plain, eastern USA is revised to a middle to late Albian age. © 2016 Elsevier B.V. Source

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