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Michal Gąsiorowski - One of the best experts on this subject based on the ideXlab platform.
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Lake–peat bog transformation recorded in the sediments of the Stare Biele mire (Northeastern Poland)
Hydrobiologia, 2009Co-Authors: Michal Gąsiorowski, Mirosława KupryjanowiczAbstract:The history of Stare Biele paleolake (northeast Poland) has been reconstructed using subfossil Cladocera remains and pollen and spores of aquatic and mire plants from a sediment core. Sediment accumulation began approximately 12,000 years ago during the Older Dryas Chronozone. Throughout the entire Late Glacial period, the basin was a small, low-trophic state lake with a developed open-water zone. A well-recorded increase in the trophic state started at the beginning of Holocene. The lake reached its highest trophic level during the early and middle Atlantic Chronozone. The first human activity in the lake catchment area occurred at this time, as recorded by fern spores and numerous charcoal grains. Repeated rises in lake water level are documented at the beginning and throughout the early part of the Younger Dryas. Two clear events of decreasing lake water levels are recorded, first during the middle part of the Younger Dryas and second in the Preboreal. Terrestrialization processes first intensified at the end of Atlantic period, which appears to correspond to a decrease in pH.
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lake peat bog transformation recorded in the sediments of the stare biele mire northeastern poland
Hydrobiologia, 2009Co-Authors: Michal Gąsiorowski, Miroslawa KupryjanowiczAbstract:The history of Stare Biele paleolake (northeast Poland) has been reconstructed using subfossil Cladocera remains and pollen and spores of aquatic and mire plants from a sediment core. Sediment accumulation began approximately 12,000 years ago during the Older Dryas Chronozone. Throughout the entire Late Glacial period, the basin was a small, low-trophic state lake with a developed open-water zone. A well-recorded increase in the trophic state started at the beginning of Holocene. The lake reached its highest trophic level during the early and middle Atlantic Chronozone. The first human activity in the lake catchment area occurred at this time, as recorded by fern spores and numerous charcoal grains. Repeated rises in lake water level are documented at the beginning and throughout the early part of the Younger Dryas. Two clear events of decreasing lake water levels are recorded, first during the middle part of the Younger Dryas and second in the Preboreal. Terrestrialization processes first intensified at the end of Atlantic period, which appears to correspond to a decrease in pH.
Kevin N Page - One of the best experts on this subject based on the ideXlab platform.
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the biostratigraphy of the upper pliensbachian toarcian lower jurassic sequence at ilminster somerset
Journal of Micropalaeontology, 2009Co-Authors: Ian Boomer, Kevin N Page, Paul R Bown, F M D Lowry, A R Lord, James B RidingAbstract:Temporary road sections for the A303 bypass at Ilminster, Somerset, revealed Upper Pliensbachian and Toarcian sediments from an alternating limestone–marl facies, in marked contrast to the limestone-dominated Dorset coast succession. The lithostratigraphy is described, with the standard ammonite zonation providing chronostratigraphical correlation. The uppermost Pliensbachian (Spinatum Chronozone) and much of the Toarcian (Serpentinum, Bifrons, Variabilis, Thouarsense and Pseudoradiosa Chronozones) of the classic Dorset coast Lower Jurassic sequence are represented by the Beacon Limestone Formation, formerly the ‘Junction Bed’ (a highly condensed carbonate deposit). The Tenuicostatum Chronozone is largely missing from the sequence. Elsewhere in southern and eastern England this interval is poorly or rarely exposed. The argillaceous units have yielded rich microfaunas and -floras (foraminifera, ostracods, calcareous nannofossils and palynomorphs), the biostratigraphical distributions of which are analysed and discussed in relation to contemporary evolutionary patterns and other UK records. This study provides an insight into the micro-biostratigraphy of the Late Pliensbachian to Toarcian interval for onshore southern England.
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the biostratigraphy of the upper pliensbachian toarcian lower jurassic sequence at ilminster somerset
Journal of Micropalaeontology, 2009Co-Authors: Ian Boomer, Kevin N Page, Paul R Bown, F M D Lowry, A R Lord, James B RidingAbstract:Temporary road sections for the A303 bypass at Ilminster, Somerset, revealed Upper Pliensbachian and Toarcian sediments from an alternating limestone–marl facies, in marked contrast to the limestone-dominated Dorset coast succession. The lithostratigraphy is described, with the standard ammonite zonation providing chronostratigraphical correlation. The uppermost Pliensbachian (Spinatum Chronozone) and much of the Toarcian (Serpentinum, Bifrons, Variabilis, Thouarsense and Pseudoradiosa Chronozones) of the classic Dorset coast Lower Jurassic sequence are represented by the Beacon Limestone Formation, formerly the ‘Junction Bed’ (a highly condensed carbonate deposit). The Tenuicostatum Chronozone is largely missing from the sequence. Elsewhere in southern and eastern England this interval is poorly or rarely exposed. The argillaceous units have yielded rich microfaunas and -floras (foraminifera, ostracods, calcareous nannofossils and palynomorphs), the biostratigraphical distributions of which are analysed and discussed in relation to contemporary evolutionary patterns and other UK records. This study provides an insight into the micro-biostratigraphy of the Late Pliensbachian to Toarcian interval for onshore southern England.
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High resolution ammonite stratigraphy of the Charmouth Mudstone Formation (Lower Jurassic: Sinemurian – Lower Pliensbachian) in South West England (UK)
2006Co-Authors: Kevin N PageAbstract:The “Lower Lias” mudrocks of the Charmouth Mudstone Formation in West Dorset coast are world famous for their ammonite faunas, which range from mid Lower Sinemurian (Semicostatum Chronozone) to Lower Pliensbachian (topmost Davoei Chronozone) in age. The succession includes significant non-sequences, however, and as certain other intervals yield only crushed and relatively poorly preserved material, much of the sequence of ammonite faunas of this interval in south-west England has remained poorly understood. Inland, however, although it has been realised for many years that some of the missing horizons reappear, the Formation is very poorly exposed and as a consequence little has been known about its detailed stratigraphy and palaeontology. The systematic recording over 40 years by Mr H.C. Prudden (Montacute) of temporary excavations in East Somerset (around 20 km north of the Dorset coast), combined with material collected by others from similar exposures has now, however, revealed a virtually complete sequence of ammonite faunas through the interval represented by the Formation including from many of the which are missing on the Dorset coast. In particular, only one subChronozone remains to be conclusively proven in the region, the terminal Sinemurian, Aplanatum SubChronozone (Raricostatum Chronozone). This faunal succession is correlated with that on the coast to provide a detailed synthesis of the sequence of ammonite biohorizons in the region, which is correlated with a contemporary Standard Zonation and high-resolution biohorizonal/ zonule scheme for interval in North-West Europe. The significance for regional and international correlations of the Lower Lias is also discussed.
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A SEQUENCE OF BIOHORIZONS FOR THE SUBBOREAL PROVINCE LOWER TOARCIAN IN NORTHERN BRITAIN AND THEIR CORRELATION WITH A SUBMEDITERRANEAN STANDARD
Rivista Italiana Di Paleontologia E Stratigrafia, 2004Co-Authors: Kevin N PageAbstract:A sequence of sub-subzonal correlative units at the level of biohorizon is described for the Subboreal Province, Lower Toarcian of North Yorkshire, north west England. Nineteen such units are recognised, as follows: Tenuicostatum Chronozone, Paltum SubChronozone ( paltum ), Clevelandicum SubChronozone ( crosbeyi, clevelandicum ), Tenuicostatum SubChronozone ( tenuicostatum ), Semicelatum SubChronozone ( semicelatum, antiquum ), Serpentinum Chronozone, Exaratum SubChronozone ( elegantulum, exaratum, elegans ), Falciferum SubChronozone ( pseudoserpentinum, falciferum ), Bifrons Chronozone, Commune SubChronozone ( ovatum , commune, athleticum ), Fibulatum SubChronozone ( turriculum, braunianus, vortex ), Crassum SubChronozone ( crassum-bifrons, crassum-semipolitum ). The presence of shared taxa permits detailed correlations to be established with submediterranean zonal schemes in more southerly areas of Europe and an equilibration of zonal boundaries across the region is therefore proposed, providing a uniformity of interpretation for the European Lower Toarcian.
Mirosława Kupryjanowicz - One of the best experts on this subject based on the ideXlab platform.
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The Late Glacial and Holocene development of vegetation in the area of a fossil lake in the Skaliska Basin (north-eastern Poland) inferred from pollen analysis and radiocarbon dating
Acta Palaeobotanica, 2013Co-Authors: Piotr Kołaczek, Monika Karpińska-kołaczek, Mirosława Kupryjanowicz, Marta Szal, Hanna Winter, Weronika Danel, Katarzyna Pochocka-szwarc, Renata Stachowicz-rybkaAbstract:The development of vegetation in the Skaliska Basin has been reconstructed on the basis of palynological analysis and radiocarbon dating (AMS technique) of 6 sites from the late phase of the Bolling- Allerod interstadial complex to modern times. Although the area covers 90 km2, the mosaic character of habitats led to the development of different patterns of vegetation changes during the Late Glacial and Holocene. Only one site located in the eastern part of the Skaliska Basin reflected the ‘pine phase’ of Allerod, and this is the oldest data on vegetation in the Skaliska Basin. Interesting discrepancies were recorded during the Younger Dryas when patches of shrublands with Juniperus were distinct around some of the sites, while steppe with Artemisia was common in others. The beginning of the Holocene brought an expansion of birch-pine forest, but around 9600 cal. BC a cold oscillation took place which was reflected in an increase in birch in the woodlands in the western and eastern part of the Skaliska Basin. In the Preboreal Chronozone elm (Ulmus) also expanded in the area but its appearance was non-synchronous. The vegetation of the Boreal Chronozone was similar in the whole area and the most characteristic feature was the rapid expansion of hazel (Corylus avellana) which displaced Betula from the most of its sites. At that time a distinct redeposition of pollen material in the Parchatka river valley was detected which was probably the effect of an increase in fluvial activity of the river (humid oscillation). The following stage of vegetation development was climax woodlands with Tilia cordata, Ulmus, Quercus, Corylus avellana, and Alnus in damp places. At the beginning of the Subboreal Chronozone the expansion of Quercus took place, which was subsequently replaced by Picea abies and partly Carpinus betulus. The pattern of Picea abies expansion distinctly presents two maxima which is characteristic of many sites in the north-eastern Poland. The Subatlantic Chronozone is represented only by the profile from the Skaliski Forest, where, because of sandy ground, Pinus sylvestris was the dominant element. Human impact was poorly reflected through the rare occurrence of pollen grains of Cerealia type in the pollen profiles spanning the time from the Subboreal Chronozone to modern times. In most profiles AMS dating produced age discrepancies, which limited the possibility of establishment of a detailed chronology. However, dates obtained from the material contaminated by mixture of glycerine, thymol and ethyl alcohol, pretreated by alcohol, showed reliable results in most cases.
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Lake–peat bog transformation recorded in the sediments of the Stare Biele mire (Northeastern Poland)
Hydrobiologia, 2009Co-Authors: Michal Gąsiorowski, Mirosława KupryjanowiczAbstract:The history of Stare Biele paleolake (northeast Poland) has been reconstructed using subfossil Cladocera remains and pollen and spores of aquatic and mire plants from a sediment core. Sediment accumulation began approximately 12,000 years ago during the Older Dryas Chronozone. Throughout the entire Late Glacial period, the basin was a small, low-trophic state lake with a developed open-water zone. A well-recorded increase in the trophic state started at the beginning of Holocene. The lake reached its highest trophic level during the early and middle Atlantic Chronozone. The first human activity in the lake catchment area occurred at this time, as recorded by fern spores and numerous charcoal grains. Repeated rises in lake water level are documented at the beginning and throughout the early part of the Younger Dryas. Two clear events of decreasing lake water levels are recorded, first during the middle part of the Younger Dryas and second in the Preboreal. Terrestrialization processes first intensified at the end of Atlantic period, which appears to correspond to a decrease in pH.
Miroslawa Kupryjanowicz - One of the best experts on this subject based on the ideXlab platform.
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lake peat bog transformation recorded in the sediments of the stare biele mire northeastern poland
Hydrobiologia, 2009Co-Authors: Michal Gąsiorowski, Miroslawa KupryjanowiczAbstract:The history of Stare Biele paleolake (northeast Poland) has been reconstructed using subfossil Cladocera remains and pollen and spores of aquatic and mire plants from a sediment core. Sediment accumulation began approximately 12,000 years ago during the Older Dryas Chronozone. Throughout the entire Late Glacial period, the basin was a small, low-trophic state lake with a developed open-water zone. A well-recorded increase in the trophic state started at the beginning of Holocene. The lake reached its highest trophic level during the early and middle Atlantic Chronozone. The first human activity in the lake catchment area occurred at this time, as recorded by fern spores and numerous charcoal grains. Repeated rises in lake water level are documented at the beginning and throughout the early part of the Younger Dryas. Two clear events of decreasing lake water levels are recorded, first during the middle part of the Younger Dryas and second in the Preboreal. Terrestrialization processes first intensified at the end of Atlantic period, which appears to correspond to a decrease in pH.
Fabrizio Cecca - One of the best experts on this subject based on the ideXlab platform.
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early toarcian jurassic belemnites from northeastern gondwana south riffian ridges morocco
Palaeontologische Zeitschrift, 2015Co-Authors: Malcolm T Sanders, Jeremie Bardin, Mohammed Benzaggagh, Fabrizio CeccaAbstract:A belemnite fauna collected in the lowermost Toarcian succession that crops out near Moulay Idriss (northern Morocco) is studied in this article. This is the first palaeontological study of Early Toarcian belemnites from Northern Africa, i.e., the northeastern margin of the Gondwana, in connexion with Tethys. Four species of the family Passaloteuthidae Naef, 1922, have been identified: Passaloteuthis bisulcata (de Blainville, 1827), Pseudohastites longiformis (Blake, 1876), Parapassaloteuthis zieteni (Mayer-Eymar, 1884) and Parapassaloteuthis sp. A. All species have been collected in lowermost Toarcian beds dated to the ammonite Polymorphum Chronozone (=Tenuicostatum Chronozone), which coincides with the belemnite Passaloteuthis bisulcata biozone. The discovery of a syntype of this zonal index is discussed. The identified species are common with Europe, thus suggesting that the onset of the belemnite provincialism in the Toarcian could post-date the earliest Toarcian Polymorphum—Tenuicostatum Chronozone. However, records of Early Jurassic belemnites are still too sparse to recognize the establishment of provincialism and the timing of its onset.
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Early Toarcian (Jurassic) belemnites from northeastern Gondwana (South Riffian ridges, Morocco)
Paläontologische Zeitschrift, 2015Co-Authors: Malcolm T Sanders, Jeremie Bardin, Mohammed Benzaggagh, Fabrizio CeccaAbstract:A belemnite fauna collected in the lowermost Toarcian succession that crops out near Moulay Idriss (northern Morocco) is studied in this article. This is the first palaeontological study of Early Toarcian belemnites from Northern Africa, i.e., the northeastern margin of the Gondwana, in connexion with Tethys. Four species of the family Passaloteuthidae Naef, 1922, have been identified: Passaloteuthis bisulcata (de Blainville, 1827), Pseudohastites longiformis (Blake, 1876), Parapassaloteuthis zieteni (Mayer-Eymar, 1884) and Parapassaloteuthis sp. A. All species have been collected in lowermost Toarcian beds dated to the ammonite Polymorphum Chronozone (=Tenuicostatum Chronozone), which coincides with the belemnite Passaloteuthis bisulcata biozone. The discovery of a syntype of this zonal index is discussed. The identified species are common with Europe, thus suggesting that the onset of the belemnite provincialism in the Toarcian could post-date the earliest Toarcian Polymorphum—Tenuicostatum Chronozone. However, records of Early Jurassic belemnites are still too sparse to recognize the establishment of provincialism and the timing of its onset. Aus der untersten Toarcium-Abfolge in der Nähe von Moulay Idriss (Nord-Marokko) wird eine Belemnitenfauna beschrieben. Dies ist die erste paläontologische Studie von Belemniten aus dem frühen Toarcium von Nordafrika, d.h. vom nordöstlichen Rand Gondwanas, der mit der Tethys in Verbindung stand. Vier Arten der Familie Passaloteuthidae Naef, 1922 wurden bestimmt: Passaloteuthis bisulcata (de Blainville, 1827), Pseudohastites longiformis (Blake, 1876), Parapassaloteuthis zieteni (Mayer-Eymar, 1884) und Parapassaloteuthis sp. A. Alle Arten stammen aus den untersten Toarcium-Schichten, die der Ammoniten Polymorphum-Chronozone (=Tenuicostatum Chronozone) angehören. Sie entspricht der Belemniten Palassoteuthis bisulcata Biozone. Die Entdeckung eines Syntyps dieses Zonen-Indexfossils wird diskutiert. Die identifizierten Arten treten auch in Europa auf, was darauf hindeutet, dass der Belemniten-Provinzialismus im Toarcium erst nach der Polymorphum ? Tenuicostatum Chronozone des frühesten Toarcium einsetzte. Allerdings sind die Belemnitenfunde des frühen Jura noch zu spärlich, um die Etablierung des Provinzialismus und den Zeitpunkt seines Einsetzens zu erkennen.
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Lower Toarcian (Jurassic) ammonites of the South Riffian ridges (Morocco): systematics and biostratigraphy
2015Co-Authors: Jeremie Bardin, Mohammed Benzaggagh, Isabelle Rouget, Franz T Fursich, Fabrizio CeccaAbstract:A rich ammonite fauna from the Lower Toarcian (Lower Jurassic) of the South Riffian ridges (northern Morocco), collected bed-by-bed from 14 new outcrops, is described. The fauna is nearly exclusively composed of already-known taxa, allowing correlation from the Chronozone down to the zonule level. Fourteen species are described, among them the new species Dactylioceras (Dactylioceras) laticostatum sp. nov. The stratigraphical interval studied spans the first Chronozone of the Toarcian, the Polymorphum Chronozone, but it remains unclear whether the Toarcian Oceanic Anoxic Event is represented in the studied succession. The Early Toarcian is mainly characterized by representatives of the family Dactylioceratidae, which are abundant but commonly crushed or deformed. Two new descriptors are proposed to describe the shell shape of crushed or incomplete specimens and have been used together with the classical ones for the taxonomic treatment of this group. A hypothesis about dimorphism in Dactylioceras (Orthodactylites) semicelatum (Simpson, 1843) and Dactylioceras (Dactylioceras) laticostatum sp. nov. is proposed.http://zoobank.org/urn:lsid:zoobank.org:pub:E7934E4A-942C-4C73-9831-22A8C0B0B89A
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Lower Toarcian (Jurassic) ammonites of the South Riffian ridges (Morocco): systematics and biostratigraphy
Journal of Systematic Palaeontology, 2014Co-Authors: Jeremie Bardin, Mohammed Benzaggagh, Isabelle Rouget, Franz T Fursich, Fabrizio CeccaAbstract:A rich ammonite fauna from the Lower Toarcian (Lower Jurassic) of the South Riffian ridges (northern Morocco), collected bed-by-bed from 14 new outcrops, is described. The fauna is nearly exclusively composed of already-known taxa, allowing correlation from the Chronozone down to the zonule level. Fourteen species are described, among them the new species Dactylioceras (Dactylioceras) laticostatum sp. nov. The stratigraphical interval studied spans the first Chronozone of the Toarcian, the Polymorphum Chronozone, but it remains unclear whether the Toarcian Oceanic Anoxic Event is represented in the studied succession. The Early Toarcian is mainly characterized by representatives of the family Dactylioceratidae, which are abundant but commonly crushed or deformed. Two new descriptors are proposed to describe the shell shape of crushed or incomplete specimens and have been used together with the classical ones for the taxonomic treatment of this group. A hypothesis about dimorphism in Dactylioceras (Orthoda...