6,164 results on '"Palynology"'
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2. The Middle Jurassic (Bajocian–Bathonian) flora of the Tabas Block, central Iran
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Maleki Saeed
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sporomorph ecogroup ,plant ecogroup ,palynology ,palaeobotany ,hojedk formation ,Geology ,QE1-996.5 - Abstract
The present study discusses the outcome of palynlogical and palaeobotanocal investigations of Middle Jurassic strata of the Tabas Block. The most commonly identified spore type is a trilete spore, Klukisporites, which accounts for 30 per cent, and the genus Ischyosporites which makes up 12 per cent of the spore collection. Plant fossils recovered from the borehole studied are indicative of a varied assemblage, starting with a diverse range of ferns and followed by Cycadophytes, Ginkgophytes and Coniferophytes. The predominance of the Lowland group in the Tabas Block during the Bajocian–Bathonian, as indicated by the Sporomorph EcoGroup (SEG) and Plant EcoGroup (PEG) models, suggests that the strata studied were laid down mainly in a lowland environment. Dinoflagellate cysts were found in locations that correspond to river and coastal ecogroups, hinting at marine influence.
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- 2024
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3. A hidden succession revealed: Cretaceous and Paleocene sediments and a native-iron-bearing lava flow in cores near Qullissat, Disko, West Greenland
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Lotte Melchior Larsen, Gunver Krarup Pedersen, Henrik Nøhr-Hansen, Asger Ken Pedersen, Jørgen A. Bojesen-Koefoed, Erik Vest Sørensen, and Sofie Lindström
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nuussuaq basin ,atane formation ,qilakitsoq member ,vaigat formation ,asuk member ,palynology ,landslides ,Geology ,QE1-996.5 ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Over long stretches of the north-east coast of Qeqertarsuaq (Disko), the sediments in the Nuussuaq Basin and their relations to the volcanic rocks are concealed beneath numerous landslides. Two cores south of Qullissat drilled by Falconbridge Ltd in 1994, targeting a native-iron-bearing igneous body assumed to be a sill, present well-preserved sections through the hidden succession. We have dated the sediments in the cores palynologically. The lower part comprises 115 m of deltaic deposits, including coal seams, of the Cretaceous Atane Formation, Qilakitsoq Member (late Turonian to early Coniacian age), which has not been recorded on Disko before. The two cores and five short coastal cliff sections are mutually correlatable and correlate further to the coal seams earlier mined at Qullissat; the coals are hereby dated for the first time. The Cretaceous rocks are overlain by 15 m of marine deposits, mainly mudstones, of the Danian Eqalulik Formation, with a hiatus of c. 24 million years. The igneous body of native-iron-bearing basaltic andesite has a thick, red-oxidised, vesiculated and brecciated top zone and is interpreted as a subaerial lava flow belonging to the Asuk Member of the Vaigat Formation. The flow has run perhaps up to 20 km from the eruption site to the sea, where it ponded and attained a thickness of 138 m, the thickest lava flow in the West Greenland Basalt Group. The flow is overlain by 22 m of non-marine sandstones and mudstones of the Atanikerluk Formation. The core correlation indicates the existence of a fault with c. 90 m vertical displacement between the two drill sites. The structural relations of the various parts of the Atane Formation along the north-east coast of Disko necessitate the assumption of another hidden, prevolcanic fault south of Qullissaaqqat.
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- 2024
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4. Integration of Ukrainian paleobotanists and palynologists into the international community of scientists
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O. A. Shevchuk, O. A. Sirenko, A. V. Ivanina, and D. O. Pustovoitova
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paleobotany ,palynology ,biostratigraphy ,phanerozoic ,conferences ,russian-ukrainian war ,ukraine ,sweden ,Geology ,QE1-996.5 - Abstract
Introduction. The European Palaeobotany and Palynology Conference is held every 4 years. At meetings and seminars of the conference, a wide range of scientific problems related to taxonomy of ancient plants, morphology, nomenclature, as well as the latest results of paleobotanical and palynological research are represented, ways of using them for stratigraphic constructions, paleogeographic, including paleoclimatic reconstructions, and the study of archaeological monuments are discussed. Formulation of the problem. A necessary aspect of today’s scientific research in Ukraine is the integration of the research results of Ukrainian scientists into the world scientific space. An important component in the implementation of this direction is the active participation of scientists in international projects and the presentation of research results at international professional conferences. The presented publication is devoted to an overview of one of these forums. Formulation of the purpose of the article. The main purpose of the article is to highlight the latest directions of the modern stage of paleobotanical and palynological research of the world scientific community, which were represented at the 11th European paleobotanical – palynological conference, as well as the characteristics of the scientific results of Ukrainian scientists, which was presented at this forum. Presenting main material. The 11th European Conference on Paleobotany and Palynology was held in Stockholm on June 19-22, 2022. The conference was jointly organized by the Swedish Museum of Natural History and Stockholm University. The head of the organizing committee and event coordinator was Professor Vivi Vaida. The conference gathered more than 240 delegates from 44 countries of the world, which proves the authority of the conference and the exit of EPPC beyond Europe to the international level. More than 180 oral scientific presentations and about 70 poster presentations were presented during the plenary and sectional meetings. The organizers of the conference condemned Russia’s invasion of Ukraine, and the support of the Ukrainian scientific community and the people of Ukraine was felt at all stages of the conference preparation. Main scientific directions of symposia work. Work during the conference took place in 35 scientific symposia of various topics, covering almost all modern aspects of paleobotany and palynology. The article provides a general description of the latest research that was discussed at the conference. Achievements of Ukrainian scientists represented at the conference. In total, scientists from Ukraine presented 2 oral reports – O. A. Shevchuk (The first Cretaceous megaspores from Ukraine) and D. O. Pustovoitova (History of palynological research of Mesozoic deposits in Ukraine) and 6 posters – O. A. Shevchuk (Paleobotanical research in Ukraine); O. A. Sirenko (Changes in the vegetation of Ukraine in the Gelasian time (by palynological data)); A. B. Ivanina, A. О. Myronova (Standardized characteristics of the Geminospora extensa Zone from the Givetian of western Ukraine); V. Р. Grytsenko and O. A. Shevchuk (On the collections of fossil plant and algae in the geological department of the National Museum of Natural History at the National Academy of Sciences of Ukraine); A. I. Martyshyn, O. A. Shevchuk (Taphonomy of tubular fossils (algae) from the deposits of the Late Ediacaran of Ukraine); N. I. Boyarina (The collection of the late Carboniferous plant fossils of the Donets Bassin in the Institute of Geological Sciences of NAS of Ukraine: general review). The scientific reports presented concerned various aspects of paleobotanical and palynological research: historical, taphonomic, stratigraphic, paleogeographic and paleoclimatic reconstructions, review of paleobotanical collections and problems of their storage in modern military conditions. The presented materials covered the results of the study of micro- and macro-plant remains from rocks of all subdivisions of the Phanerozoic (Paleozoic, Mesozoic, Cenozoic), as well as the Neoproterozoic (Ediacaran). Conclusions. At the conference, during the plenary and sectional meetings, considerable attention was paid to the results of research devoted to climate changes and their impact on the biota of high latitudes in the past, as well as reconstructions of the paleogeographic conditions of the formation of deposits of different ages, especially Holocene. Attention is focused on the need to develop new research methods, in particular 3D modeling of paleontological objects, popularization of paleobotany and palynology achievements, preservation of paleontological monuments, interaction of amateur paleontologists with professional paleontologists and scientific institutions and organizations.
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- 2023
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5. RECENT RETIREE.
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GEOLOGISTS ,GEOLOGY ,SEDIMENTOLOGY ,PALYNOLOGY - Published
- 2024
6. New Field Conference StoryMap.
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Smale, Jody
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CONFERENCES & conventions ,GEOLOGY ,GEOLOGISTS ,PALYNOLOGY ,SEDIMENTOLOGY - Published
- 2024
7. Occupancy models reveal regional differences in detectability and improve relative abundance estimations in fossil pollen assemblages
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Lawing, A Michelle, Blois, Jessica L, Maguire, Kaitlin C, Goring, Simon J, Wang, Yue, and McGuire, Jenny L
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Earth Sciences ,Physical Geography and Environmental Geoscience ,Geology ,Detectability ,Occupancy ,Pcount ,Relative abundance ,Spatial ecology ,Palynology ,History and Archaeology ,Paleontology ,Earth sciences ,History ,heritage and archaeology - Published
- 2021
8. What Are the Most Effective Proxies in Identifying Storm‐Surge Deposits in Paleotempestology? A Quantitative Evaluation From the Sand‐Limited, Peat‐Dominated Environment of the Florida Coastal Everglades
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Qiang Yao, Kam‐biu Liu, Zhenqing Zhang, Erika Rodrigues, Marcelo Cohen, Kanchan Maiti, and Yang Yang
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paleotempestology ,sedimentology ,geochemistry ,stable isotope ,palynology ,Hurricane Wilma ,Geophysics. Cosmic physics ,QC801-809 ,Geology ,QE1-996.5 - Abstract
Abstract Although many studies have attempted to reconstruct millennial‐scale hurricane patterns using various proxy‐based methods, it is still unclear what the most effective proxies are to identify storm surge deposits in different environmental settings. This study quantitatively compares the application of grain‐size, loss‐on‐ignition, stable isotopes, X‐ray fluorescence, and palynological proxies in paleotempestology from an organic‐rich environment in the Florida Everglades. The nonparametric tests indicate that only 9 among the 27 parameters (mean diameter, %water, %organic, %carbonate, Ca, Sr, Ca/Ti, Cl/Br, and marine microfossils) exhibited significant differences between storm‐surge and in situ deposits. The principal component analysis shows that five marine indicators (Sr, Ca, Ca/Ti, %Carbonate, and Marine microfossils) have the closest association with the allochthonous samples, while Cl/Br and Mz are the most sensitive proxies in low‐ and high‐energy environments, respectively. Moreover, organic geochemical proxies (e.g., δ13C and δ15N of bulk sedimentary organic matter) are ineffective for identifying storm‐surge deposits in organic‐rich mangrove environments.
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- 2023
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9. NEW STAFF MEMBER.
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SEDIMENTOLOGY ,GEOLOGY ,GEOLOGISTS ,PALYNOLOGY - Published
- 2024
10. BIOZONATION AND AGE RECONSTRUCTION OF 4000FT TO 4540FT SECTION OF WELL-X, NIGER DELTA, NIGERIA
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Otto A. Ihunda, Ifiok M. Ibanga, and Ndubuisi Ukpabi
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palynology ,biozonation ,range chart ,palynomorphs ,late miocene ,Geology ,QE1-996.5 - Abstract
Biozonation and Age reconstruction of an offshore Well-X in the Niger Delta was carried out using10composite ditch cutting samples, Palynological studies was carried out on the samples to determine the age of the formation penetrated in the well, generate a range chart for the palynomorphs and generate biozones. The samples were described and prepared using the standard non mineral acid method of preparing Palynological samples. The interval studied was between 1219m (4000ft) -1384m (4540ft) thickness, belonging to the Agbada Formation which is of late Miocene. Lithologically the section penetrated by the well varies from sandstone bed to shaly bed. One biozone of the SPDC scheme P850 has been erected. The P850 zone palynomorphs observed within this interval which coincides with the P860 subzone include abundance of Zonocostitesramonae, rich occurrence of Stereisporitessp, Retibrevitricolporites obodoensis, and Psilatricolporites crassus, scanty Nympheapollislotus, and Multiareolites formosus as well as the presence of Peregrinipollis nigericus. The age of the sediment is of the late Miocene.
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- 2022
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11. Early Cretaceous (Albian) spores and pollen from the Glen Rose Formation of Texas and their significance for correlation of the Potomac Group
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Tanrikulu, Sinem, Doyle, James A, and Delusina, Irina
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Cretaceous ,Albian ,Texas ,palynology ,angiosperms ,stratigraphy ,Potomac ,Geology ,Paleontology - Abstract
Because the Gulf Coast Lower Cretaceous is dated by ammonites, it has great potential as a reference section for correlating continental sequences such as the Potomac Group and dating events in the rise of angiosperms. Middle Albian terrestrial palynofloras from Oklahoma have been described in detail, but the early Albian interval, represented in the Glen Rose Formation of Texas, is less well known. Samples from two localities on the Paluxy River, which correlate with horizons containing late early Albian ammonites, are dominated by Classopollis and Exesipollenites, but angiosperm pollen is the next most common terrestrial element, and there are several index spore species for Zone II in the Potomac Group. Among the angiosperms, reticulate monosulcates are most common and diverse, but there are also several tricolpate species. Stratigraphically important angiosperms include the Clavatipollenites rotundus group and reticulate tricolpates, which appear in the upper part of Potomac Zone I and the dated earliest Albian of England and Portugal. However, there are also tricolpates with striate-reticulate sculpture, a pollen type that is not known from upper Zone I but appears in the late early Albian of Portugal. This assemblage contrasts with floras from Potomac Zone II and the middle Albian (lower Fredericksburg Group) of Oklahoma, where tricolpates overtook monosulcate angiosperms in species diversity. These results confirm arguments based on the Portuguese section that there is a significant hiatus between Potomac Zones I and II, and that this gap is at least partly late early Albian. The dominance of Classopollis and Exesipollenites and the occurrence of isolated Northern Gondwanan elements (Sergipea, Tucanopollis) suggest that Texas lay in a transition zone between Southern Laurasia and the hotter and drier Northern Gondwana province, but regional studies are needed to disentangle geographic and climatic factors from effects of the lagoonal local environment.
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- 2018
12. Paleoceanography and dinoflagellate cyst stratigraphy across the Lower–Middle Pleistocene Subseries (Calabrian–Chibanian Stage) boundary at the Chiba composite section, Japan
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Eseroghene J. Balota, Martin J. Head, Makoto Okada, Yusuke Suganuma, and Yuki Haneda
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Dinoflagellate cysts ,Paleontology ,Palynology ,Paleoceanography ,MIS 19 ,GSSP ,Geography. Anthropology. Recreation ,Geology ,QE1-996.5 - Abstract
Abstract A dinoflagellate cyst record from the highly resolved Chiba composite section in Japan has been used to reconstruct sea-surface paleoceanographic changes across the Lower–Middle Pleistocene Subseries (Calabrian–Chibanian Stage) boundary at the global stratotype, constituting the first detailed study of this microfossil group from the Pleistocene of the Japanese Pacific margin. Cold, subarctic water masses from 794.2 ka gave way to warming and rapid retreat of the Subpolar Front at 789.3 ka, ~ 2000 years before the end of Marine Isotope Stage (MIS) 20. Throughout the fully interglacial conditions of MIS 19c, assemblages are consistent with warm sea surface temperatures but also reveal instability and latitudinal shifts in the Kuroshio Extension system. The abrupt dominance of Protoceratium reticulatum cysts between 772.9 and 770.4 ka (MIS 19b) registers the influence of cooler, mixed, nutrient-rich waters of the Kuroshio–Oyashio Interfrontal Zone resulting from a southward shift of the Kuroshio Extension. Its onset at 772.9 ka serves as a local ecostratigraphic marker for the Chibanian Stage Global Boundary Stratotype Section and Point (GSSP) which occurs just 1.15 m (= 1300 years) below it. An interval from 770.1 ka to the top of the examined succession at 765.8 ka (MIS 19a) represents warm, presumably stratified but still nutrient-elevated surface waters, indicating a northward shift of the Kuroshio Extension ~ 5 kyrs after the termination of full interglacial conditions on land.
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- 2021
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13. Early land plant remains from the uppermost Ordovician–?lowermost Silurian Cedarberg Formation of South Africa
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Charles H. Wellman, Cameron R. Penn-Clarke, and Claire Browning
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soom shale ,hirnantian ,gondwana ,glaciation ,palynology ,cryptospores ,Geology ,QE1-996.5 - Abstract
The Cape Supergroup forms a regionally extensive and extremely thick Ordovician to Carboniferous succession of sedimentary rocks in southwestern South Africa. It includes the LowerâMiddle Ordovicianâlowermost Devonian Table Mountain Group, which incorporates the uppermost Ordovician Soom Shale Lagerstätte (within the Cedarberg Formation). The Soom Shale Lagerstätte accumulated in an unusual cold-water setting, associated with the decaying South African ice sheet, towards the end of the Hirnantian glaciation. The deposits of this glacial marine environment, characterised by anoxic bottom waters, preserve a highly unusual marine biota. It includes specimens exhibiting exceptional preservation of their soft tissues in clay minerals. Overlying deposits of the Soom Shale are shales and thin sandstones ascribed to the Disa Member that accumulated in a shoreface-shelf setting. Associated with these deposits are relict Soom taxa, in addition to a handful of Clarkeia-type brachiopod faunas, suggesting a probable earliest Silurian age for the upper part of the Cedarberg Formation. Previous palynological investigations of the Soom Shale have yielded typical marine elements, including chitinozoans, scolecodonts and rare acritarchs, but also common terrestrial elements in the form of dispersed spore tetrads. The latter are historically important as they represent an early report, by Jane Gray and colleagues, of dispersed cryptospore tetrads and were the first evidence for early land plants from Africa south of the Sahara (Ordovician eastern Gondwana at 30Ë S). Herein we report on a palynological investigation of an exposure of the Cedarberg Formation from the northernmost outcrops of the Cape Supergroup at Matjiesgoedkloof, Western Cape Province. Recently the sedimentology and ichnology of the underlying ice-marginal shallow-marine deposits of the Pakhuis Formation were described. Although macrofossils have not been recovered from these strata, they yield a fascinating ichnofauna that is diverse and disparate, comprising trackways and burrows. These show colonisation of glacial deposits by makers of burrows and trackways that lived in brackish water conditions as ice sheets retreated. Our palynological investigation yielded assemblages of abundant and well-preserved palynomorphs. Although of moderateâhigh thermal maturity, they are much less coalified than palynomorphs from the more southerly exposures. Surprisingly, the assemblages are dominated by land plant spores with extremely rare, if any, marine palynomorphs. This may be a consequence of high freshwater influx from the decaying ice sheetâs glaciers excluding normal marine biota (although the ichnological evidence demonstrates the presence of at least some organisms). The dispersed spore assemblage is somewhat unusual in that it is dominated by tetrads to the exclusion of monads and dyads. Coeval assemblages from similar palaeolatitudes in Gondwana (e.g. from the Arabian Plate) are far more diverse. This possibly reflects the close proximity of the vegetation to the ice sheet.
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- 2023
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14. Upper Ordovician chronostratigraphic correlation between the Appalachian and Midcontinent basins
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Cristiana J. P. Esteves, Patrick I. McLaughlin, Alyssa M. Bancroft, Thomas W. Wong Hearing, Mark Williams, Jahandar Ramezani, Poul Emsbo, and Thijs R. A. Vandenbroucke
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holostratigraphy ,palynology ,graptolites ,conodonts ,stable carbon isotopes ,katian ,Geology ,QE1-996.5 - Abstract
Study of a subsurface core (named F688) from northern Indiana provides integrated data sets linking Katian chronostratigraphic records of the Appalachian and Midcontinent basins. The F688 core shows a variety of shallow- and deep-water facies containing numerous, well-preserved and zonally significant fossil species and diagnostic chemostratigraphic patterns. The succession belonging to the Cincinnatian Regional Stage in the F688 core is 210 m thick. Detailed benchtop examination of the succession revealed several phosphatic intervals, rich brachiopod faunas, multiple graptolitic horizons, and at least two tephras. Elemental analysis was conducted at 60 cm spacing quantifying lithofacies composition. Based on these results, the succession was assigned to six previously defined lithostratigraphic units (Kope, Waynesville, Liberty, Whitewater, Elkhorn, and Fort Atkinson formations). This lithostratigraphic succession shares components with both the Appalachian and Midcontinent basins, suggesting deposition near their shared margin. Twenty samples yielded abundant, well-preserved, low-diversity conodont assemblages with long-ranging taxa that clearly demarcate the position of the OrdovicianâSilurian boundary at the top of the succession in the core. More than fifty palynologic samples, targeting graptolite-bearing intervals, were processed for chitinozoans and produced important new insights. The Kope Formation contains the chitinozoan species Belonechitina kjellstromi, Hercochitina downiei, and Clathrochitina sp. nov., co-occurring with a graptolite assemblage suggestive of the Geniculograptus pygmaeus Zone. Samples from the overlying Waynesville Formation produced graptolites indicative of the upper G. pygmaeus to Paraorthograptus manitoulinensis zones co-occurring with the long-ranging chitinozoan species Belonechitina micracantha and Plectochitina spongiosa as well as several new species of the genera Tanuchitina and Hercochitina. Higher in the core, the Liberty, Whitewater, Elkhorn, and Fort Atkinson formations yielded chitinozoan species characteristic of the upper Katian biozones of Anticosti Island and Nevada, such as Tanuchitina anticostiensis, Hercochitina longi, and Eisenackitina ripae. Results of δ13Ccarb analysis reveal partial preservation of the Kope, Waynesville, and Elkhorn excursions. A tephra in the rising limb of the Waynesville Excursion yielded needle-shaped clear zircons that will provide a high-precision U-Pb age. The Fort Atkinson Formation is overlain by the Brassfield Formation containing Silurian conodonts and δ13Ccarb values suggesting an Aeronian age. Chronostratigraphic data from our study of the F688 core resolves longstanding uncertainty about correlations between strata of Katian Age in the Appalachian and Midcontinent basins. Integration of core F688 with our other regional chronostratigraphic data in the Midcontinent Basin demonstrates that the Fort Atkinson Formation of the Indiana and Illinois subsurface is age equivalent to the Fernvale Formation of Tennessee, Arkansas, and Oklahoma. Across this area, the Fernvale is overlain by graptolitic shales of the uppermost P. manitoulinensis to basal Dicellograptus complanatus graptolite zones. By contrast, the type Fort Atkinson Formation of Iowa is interpreted to occur completely within the younger D. complanatus Zone. These regional correlations taken as a whole suggest that the uppermost Katian (all of Ka4) and all but the uppermost Hirnantian are missing throughout much of the Appalachian Basin. By contrast, the Midcontinent Basin contains a much more complete upper Katian and Hirnantian succession. Our comprehensive approach is correcting temporal miscorrelation and providing robust chronostratigraphic context for study of biogeochemical events, which will further enable us to disentangle proxy data and identify the processes that drove the Katian diversity peak and culminated in the Late Ordovician mass extinction.
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- 2023
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15. Frans Florschütz as founding father of pollen analysis in the Netherlands, and expansion of palynology into the tropics.
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Hooghiemstra, Henry and Richards, Keith
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PALYNOLOGY , *FOSSIL pollen , *PETROLEUM prospecting , *SOIL science , *GEOLOGY - Abstract
Frans Florschütz (1887‒1965) developed pollen analysis in the Netherlands as a biostratigraphical tool on the interface between geology, palaeobotany, soil science and climate history. He was involved in agricultural practice and the building of large infrastructure. Florschütz established centres of pollen analysis at the universities in Wageningen (1924) and Utrecht (1928), was appointed professor in Leiden (1948) and after retirement founded a chair in pollen analysis in Nijmegen (1960). The botanical institute in Utrecht was Florschütz' alma mater where he supervised students over two decades. Since 1947 Florschütz trained micropalaeontologists how to use fossil pollen as a biostratigraphical tool in oil industry. He inspired Jonker in Utrecht and Zagwijn in Leiden. Several of his students focused on tropical areas and used applied and academic pollen analysis to explore tropical ecosystems, such as Polak (1930s) and Muller (1950s) in southeast Asia, Van Zinderen Bakker (1950s) in southern Africa, Van der Hammen (1950s) in northern South America, Van Zeist and Bottema (1960s) in the Middle East. He stimulated Shell to be a pioneer in using pollen-based stratigraphy in oil exploration in the tropics. In the late 1940s and 1950s biostratigraphers Germeraad, Hopping, Kuyl, Muller and Waterbolk studied samples from the Caribbean, Nigeria and British Borneo in Shell's Pollen Laboratories in Maracaibo (Venezuela) and in The Hague. In 1944 'pollen analysis' was renamed 'palynology' for good reasons. Laboratory practice in applied research developed differently from academic palynology leading to a hybrid research field. Implications are briefly discussed. [ABSTRACT FROM AUTHOR]
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- 2022
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16. Paleobotanical and palynological evidence for the age of the Matzitzi Formation, Mexico
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Villanueva-Amadoz, Uxue, Navarro, Marycruz Gerwert, Juncal, Manuel A., and Diez, José B.
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Paleobotany ,Palynology ,Matzitzi Formation ,Lonesomia mexicana ,Mexico ,Geophysics. Cosmic physics ,QC801-809 ,Chemistry ,QD1-999 ,Geology ,QE1-996.5 - Abstract
This study addresses some of the stratigraphical problems of the Matzitzi Formation of Puebla and Oaxaca States in Mexico. The age assignment for this unit is controversial although most researchers today accept a Leonardian age (Kungurian, 279.3–272.3 Ma) based on the presence of the gigantopterid Lonesomia mexicana Weber. However, after re-examination of the holotype and two paratypes, the absence of diagnostic taxonomic characters prevents the assignment of this fossil type species to the gigantopterid group. Excluding the presence of gigantopterids in this formation, the macroflora seems to be Permian in age. Samples were collected for palynological analysis to determine the age of the formation. Studied palynological assemblages seem to be reworked and are represented by 18 fossil taxa assigned to the following genera: Calamospora, Deltoidospora, Densosporites, Granulatisporites, Laevigatosporites, Latipulvinites, Lophotriletes, Platysaccus, Punctatosporites, Raistrickia, Schopfipollenites, Thymospora, Triquitrites, Verrucosisporites, and Vesicaspora. Described palynomorphs are likely Late Pennsylvanian according to the presence of Latipulvinites kosankii and Thymospora thiessenii. The biostratigraphic and geochronologic age disparities should be solved in the future.
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- 2021
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17. State of the art of Triassic palynostratigraphical knowledge of the Cantabrian Mountains (N Spain)
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Juncal, Manuel A., Diez, José B., De la Horra, Raúl, Barrenechea, José F., Borruel-Abadía, Violeta, and López-Gómez, José
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Palynology ,Ladinian ,Carnian ,Norian ,Rhaetian ,Geophysics. Cosmic physics ,QC801-809 ,Chemistry ,QD1-999 ,Geology ,QE1-996.5 - Abstract
The present-day Cantabrian Mountains (North Spain) represent the western continuation of the Pyrenean-Cantabrian Orogen, which arose from a Cenozoic collision between the Iberian and Eurasian plates. The early Alpine sedimentary record of the Cantabrian basin is represented by the latest Carboniferous-Permian and Triassic rocks, mostly of continental origin. A lack of palaeontological data has led, until recently, to erroneous interpretations of the stratigraphic position of this sedimentary record. Within the framework of the Triassic sedimentary record in northern Spain, the precise age of six samples was determined and they were grouped into four palynological assemblages according to their taxonomic composition. The study of these assemblages includes a review of all the Triassic assemblages published to date as regards the Cantabrian Mountains, thereby optimising our Triassic palynostratigraphical knowledge of this area enabling comparisons with other Triassic assemblages of Central and SW Europe.
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- 2020
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18. Palynology and stratigraphy of the thick evaporate-bearing Shashi Formation in Jiangling Depression, Jianghan Basin of South China, and its paleoclimate change
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Chun-lian Wang, Cheng-lin Liu, Jiu-yi Wang, Xiao-can Yu, and Kai Yan
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Palynology ,Geological age of evaporate ,Sylvite ,Paleocene ,Paleoclimate ,Shashi Formation ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Geology ,QE1-996.5 - Abstract
ABSTRACT: In the greater inland Jianghan Basin of South China, three salt depressions are lacking accurate geological times, of which Jiangling Depression is the largest. Evaporites are important records of paleoclimate, however, the geological ages of evaporates are very difficult to be determined because often evaporates have scare macrofossils and microfossils. Nonmarine Cretaceous to Tertiary halite deposits interbedded with mudstones are widely distributed in China. Paleocene-Eocene Thermal Maximum had very high temperatures and attracted strong interests of geologists because these times can be compared with future climate change because of global warming. However, previous studies focused on marine sediments found that during the Paleocene-Early Eocene, massive evaporate deposits formed in Jiangling depression of the Jianghan Basin. In this paper, the authors show that the Shashi Formation halite deposits formed in the Paleocene according to palynology. Most of these palynology fossils are arid types, so the massive evaporites in the Jiangling depression could be closely related to the hot Paleocene climate. High temperatures during the Paleocene contributed to the formation of the massive evaporates in the Jiangling Depression, until sylvite was the result.
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- 2020
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19. Evidence of pollen transport by the Sanaga River on the Cameroon shelf
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Bengo, Martin Darius, Elenga, Hilaire, Maley, Jean, and Giresse, Pierre
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Palynology ,Pollen ,Savanna ,Forest ,River transport ,Sediments ,Sanaga ,Cameroon ,Geophysics. Cosmic physics ,QC801-809 ,Chemistry ,QD1-999 ,Geology ,QE1-996.5 - Abstract
Thirty-eight samples were taken from the banks of the Sanaga River and its main tributaries draining different plant ecosystems, but also from rivers in the coastal basins of Cameroon. This study aims to characterize the origins of pollen and the dominant mode of transport of pollen inputs to the continental shelf. The classical method of pollen spectra analysis and multivariate statistical analysis revealed three groups of samples corresponding to the three main ecosystems in which the samples were taken. Pollens typical of the northern savannas are found in the spectra of samples taken further downstream from the Sanaga River in forest areas and not in samples from rivers draining mainly the forested coastal basins. The level of similarity between groups and the spatial evolution of spectra from upstream to downstream are related to the fluvial transport of pollen.
- Published
- 2020
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20. Middle-Upper Triassic stratigraphy and structure in the Alt Palància region (eastern Iberian Chain): A multidisciplinary approach
- Author
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F. Ortí, J.Guimerà, and A.E. Götz
- Subjects
triassic ,stratigraphy ,structural geology ,palynology ,isotopy ,iberian chain ,Science ,Geology ,QE1-996.5 - Abstract
The present study provides new data of the Middle-Upper Triassic successions and their deformation in the eastern Iberian Chain, where contractional tectonics during the Cenozoic disrupted this Mediterranean type of Triassic rocks. The succession, divided into three Muschelkalk units, was studied in the Alt Palància area. In this area, both the lower and upper Muschelkalk consist of two main types of sub-units, those made up of carbonate and those of carbonate-marl alternation. The marked similarity observed between the evaporite units of the middle Muschelkalk and the Keuper humpers their unambiguous discrimination in the field. The integration of geological mapping, stratigraphic logging, palynological dating and gypsum isotope analysis carried out provided that: i) a change in the structural style, facies, and depositional thickness occurs across a SW to NE transect at both sides of the Espina-Espadà Fault, providing evidence for the extensional activity of this major structure; ii) palynological data assign Anisian age to the Röt facies and the lower and the middle Muschelkalk units, and Ladinian to the upper Muschelkalk unit; iii) the δ34SCDT and δ18OSMOW values of gypsum reveal as a useful proxy to discriminate between the middle Muschelkalk (δ34S: 15.6 to 17.8‰) and the Keuper (δ34S: 14 to 15.5‰) units; and iv) the isotopic signature also helps to identify clayey-marly gypsiferous outcrops made up of the two evaporite facies due to tectonic juxtaposition. These results confirm the Mediterranean type of Triassic rocks for the entire Alt Palància and other areas to the NE. This multidisciplinary approach reveals as a robust methodology to study Triassic basins in Iberia and to other geological domains where the carbonate-evaporite successions have been greatly disrupted by tectonism.
- Published
- 2020
- Full Text
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21. Climate and Atlantic sea-level recorded in Southwestern Spain from 6.3 to 5.2 Ma. Inferences on the Messinian Crisis in the Mediterranean.
- Author
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Suc Jean-Pierre, Fauquette Séverine, Warny Sophie, Jiménez-Moreno Gonzalo, and Do Couto Damien
- Subjects
stratigraphy ,palynology ,climate ,climatostratigraphic relationships ,sea-level changes ,two steps of the messinian crisis ,Geology ,QE1-996.5 - Abstract
The Mio-Pliocene succession of Andalusia on the Atlantic coast (Guadalquivir Basin) is known as one of the former stratotype candidate for the Andalusian Stage, proposed during the seventies as the last stage of the Miocene. Its type section is located in Carmona, east of Seville. Our investigation includes the drilling of three cored boreholes, which provide bio- and magnetic-stratigraphic data in complement to pre-existing industrial information, and a high-resolution palynological analysis (pollen grains, spores and dinoflagellate cysts). The pollen flora and its climatic quantification provide the mean to correlate the section to the oxygen isotope curve from the Montemayor-1 borehole, located about 80 km to the West of Carmona. The variations in the ratio between dinoflagellate cysts and pollen grains are used to identify high and low oceanic levels, consistently with a recent paleobathymetric reconstruction based on foraminifera: the two lowest levels being successively marked by the deposit of a littoral calcarenite (the Calizza Tosca Formation) then by a subaerial erosive episode. Based on the correlation with the Montemayor-1 regional drilling, the two major lowerings in oceanic level observed at Carmona are linked with the two episodes of the Messinian Crisis. The interlocking position of the high-energy sandstone deposits inscribed in the Messinian valley leads to an assessment of a drop in the global oceanic level of about 114 m at the beginning of the paroxysm of the Messinian Crisis, amplitude to be moderated with respect to the potential effect of isostatic readjustements due to the Messinian Crisis. Comparisons are discussed with the amplitude of the Messinian Erosional Surface in the West-Alboran Basin which potentially remained suspended and fed with Atlantic waters during the height of the crisis and isolated from the rest of the almost totally dried Mediterranean Basin. The quantified climate constructed from the pollen records confirms that dry conditions existed before the Messinian Crisis in Southern Mediterranean latitudes including the Atlantic side, making the Mediterranean Sea climatically predisposed to desiccation. Atlantic sea-level variations observed in the Guadalquivir region and measured at Carmona suggest that global glacio-eustatism somewhat facilitated the onset and completion of the Messinian Crisis in the Mediterranean Basin. At last, this work allows to discriminate two regional erosive events: the first one, dated at 5.60 Ma, of fluvial origin in relation with global eustasy; the second one, submarine, occurred just before 5.33 Ma, and referred to the strain exerted by the Guadalquivir olistostrome.
- Published
- 2023
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22. Recognising angiosperm clades in the Early Cretaceous fossil record
- Author
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Doyle, James A
- Subjects
palaeobotany ,palynology ,Cretaceous ,angiosperms ,phylogeny ,Geology ,Biological Sciences ,Ecology ,Evolutionary Biology ,Paleontology - Abstract
Studies of the earliest Cretaceous angiosperms in the 1970s made only broad comparisons with living taxa, but discoveries of fossil flowers and increasingly robust molecular phylogenies of living angiosperms allow more secure recognition of extant clades. The middle to late Albian rise of tricolpate pollen and the first local dominance of angiosperm leaves mark the influx of near-basal lines of eudicots. Associated flowers indicate that palmately lobed ‘platanoids’ and Sapindopsis are both stem relatives of Platanus, while Nelumbites was related to Nelumbo (also Proteales) and Spanomera to Buxaceae. Monocots are attested by Aptian Liliacidites pollen and Acaciaephyllum leaves and Albian araceous inflorescences. Several Albian–Cenomanian fossils belong to Magnoliidae in the revised monophyletic sense, including Archaeanthus in Magnoliales and Virginianthus and Mauldinia in Laurales, while late Barremian pollen tetrads (Walkeripollis) are related to Winteraceae. In the basal ANITA grade, Nymphaeales are represented by Aptian and Albian flowers and whole plants (Monetianthus, Carpestella and Pluricarpellatia). Epidermal similarities of lower Potomac leaves to woody members of the ANITA grade are consistent with Albian flowers assignable to Austrobaileyales (Anacostia). Aptian to Cenomanian mesofossils represent both crown group Chloranthaceae (Asteropollis plant) and stem relatives of Chloranthaceae and/or Ceratophyllum (Canrightia, Zlatkocarpus, Pennipollis plant and possibly Appomattoxia).
- Published
- 2015
23. PALYNOLOGY OF THE PERMIAN OF THE MAKHTESH QATAN-2, RAMON-1 AND BOQER-1 BOREHOLES ARQOV FORMATION, NEGEV, ISRAEL
- Author
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MICHAEL H. STEPHENSON and DORIT KORNGREEN
- Subjects
Permian ,palynology ,taxonomy ,Israel ,Arqov Formation. ,Geology ,QE1-996.5 ,Paleontology ,QE701-760 - Abstract
Palynological assemblages from cores 11 to 14 of Makhtesh Qatan-2, core 3 of Ramon-1 and core 3 of Boqer-1 boreholes from the Arqov Formation of the subsurface of the Negev, southern Israel, suggest that at least part of the Arqov Formation can be characterised by Cedripites priscus, Reduviasporonites chalastus and particularly Pretricolpipollenites bharadwajii, while the Saad Formation contains a slightly less diverse assemblage lacking the three taxa above. Palynological evidence is broadly consistent with other palaeontological evidence suggesting that the Saad Formation is in part likely to be Wuchiapingian in age, and the Arqov Formation is at least in part Changhsingian. These conclusions are tentative because core data is restricted to very few well penetrations and a total lack of surface exposure of the Permian.
- Published
- 2021
- Full Text
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24. Spatiotemporal relationships among Late Pennsylvanian plant assemblages: Palynological evidence from the Markley Formation, West Texas, U.S.A.
- Author
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Looy, Cindy V and Hotton, Carol L
- Subjects
Environmental change ,Markley Formation ,Palaeoecology ,Palynology ,Pennsylvanian ,Texas ,Geology ,Paleontology - Abstract
The Pennsylvanian lowlands of western Pangea are best known for their diverse wetland floras of arborescent and herbaceous ferns, and arborescent horsetails and clubmosses. In apparent juxtaposition, a very different kind of flora, dominated by a xerophilous assemblage of conifers, taeniopterids and peltasperms, is occasionally glimpsed. Once believed to represent upland or extrabasinal floras from well-drained portions of the landscape, these dryland floras more recently have been interpreted as lowland assemblages growing during drier phases of glacial/interglacial cycles. Whether Pennsylvanian dryland and wetland floras were separated spatially or temporally remains an unsettled question, due in large part to taphonomic bias toward preservation of wetland plants. Previous paleobotanical and sedimentological analysis of the Markley Formation of latest Pennsylvanian (Gzhelian) age, from north central Texas, U.S.A, indicates close correlation between lithofacies and distinct dryland and wetland megaflora assemblages. Here we present a detailed analysis one of those localities, a section unusual in containing abundant palynomorphs, from the lower Markley Formation. Paleobotanical, palynological and lithological data from a section thought to represent a single interglacial/glacial phase are integrated and analyzed to create a complex picture of an evolving landscape. Megafloral data from throughout the Markley Formation show that conifer-dominated dryland floras occur exclusively in highly leached kaolinite beds, likely eroded from underlying soils, whereas a mosaic of wetland floras occupy histosols, ultisols, and fluvial overbank deposits. Palynological data largely conform to this pattern but reveal a more complex picture. An assemblage of mixed wetland and dryland palynofloral taxa is interpolated between a dryland assemblage and an overlying histosol containing wetland taxa. In this section, as well as elsewhere in the Markley Formation, kaolinite and overlying organic beds appear to have formed as a single genetic unit, with the kaolinite forming an impermeable aquiclude upon which a poorly drained wetland subsequently formed. Within a single inferred glacial/interglacial cycle, lithological data indicate significant fluctuations in water availability tracked by changes in palynofloral and megafloral taxa. Palynology reveals that elements of the dryland floras appear at low abundance even within wetland deposits. The combined data indicate a complex pattern of succession and suggest a mosaic of dryland and wetland plant communities in the Late Pennsylvanian. Our data alone cannot show whether dryland and wetland assemblages succeed one another temporally, or coexisted on the landscape. However, the combined evidence suggests relatively close spatial proximity within a fragmenting and increasingly arid environment.
- Published
- 2014
25. Penultimate interglacial palynology of Flanders
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Filip Van Beirendonck, Nathalie Van der Putten, Cyriel Verbruggen, and Earth and Climate
- Subjects
Archeology ,Global and Planetary Change ,late Middle Pleistocene ,Northwest Europe ,Geology ,SDG 14 - Life Below Water ,Paleoclimatology ,Palynology ,Ecology, Evolution, Behavior and Systematics - Abstract
There are no Saalian Stage pollen records in Northwest Europe that not only cover an entire interglacial complex but also have been successfully correlated down to marine isotope substage level. The presented pollen record fills this knowledge gap. Three pollen sequences, sampled from a well-preserved Saalian Stage river terrace near Brussels (Belgium), together span most of an interglacial complex: two interglacial cycles and one interstadial separated by colder intervals. To date the pollen data, the authors present a multi-proxy supported river evolution model through which the correlation of the pollen record with the penultimate interglacial complex (Marine Isotope Stage (MIS) 7) becomes apparent. The authors further illustrate homotaxis—defined as the similarity between pollen diagrams that are not necessarily contemporaneous—by comparing MIS 7 with MIS 5 pollen data from the same area, convincingly curve-match the pollen record with marine isotope data, and point to similarities between Southern and Northwest European vegetation dynamics and climate variability during MIS 7.
- Published
- 2023
26. Nothofagus and the associated palynoflora from the Late Cretaceous of Vega Island, Antarctic Peninsula
- Author
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Edgardo Romero, Cecilia R. Amenábar, María C. Zamaloa, and Andrea Concheyro
- Subjects
antarctica ,vega island ,cretaceous ,nothofagaceae leaves ,palynology ,Geology ,QE1-996.5 - Abstract
Nothofagaceae fossil leaves and an associated palynoflora from Late Cretaceous sediments of Vega Island, eastern Antarctic Peninsula, are presented. The leaves are described as Nothofagus sp. 1 and Morphotype LDB 1, and come from the Snow Hill Island (late Campanian-early Maastrichtian) and the López de Bertodano (late Maastrichtian) formations, respectively. The palynoflora obtained from levels immediately above and below the Nothofagus sp. 1 and in the same horizon as the Morphotype LDB 1, included terrestrial and marine elements. In the palynoflora associated with Nothofagus sp. 1, conifers are dominant and pollen grains with Nothofagus affinity are represented by four species: Nothofagidites kaitangataensis (Te Punga) Romero 1973 and Nothofagidites senectus Dettmann and Playford 1968, which belong to the ancestral pollen type, as well as Nothofagidites dorotensis Romero 1973 and Nothofagidites sp. of the brassii-type. Cryptogamic spores, marine dinoflagellate cysts and algae, among others, are part of the assemblage. The palynoflora associated with the Morphotype LDB 1 also contains abundant conifer and angiosperm pollen grains with N. dorotensis as the only Nothofagus species recorded. Marine dinoflagellate cysts are scarce while fungi and phytodebris are common elements. The joint presence of marine and non-marine palynomorphs supports a probable nearshore environment at time of deposition for both units. Pollen and spore evidence suggests a mixed conifer and angiosperm forest, with Podocarpaceae and Nothofagus as the main components, and ferns, lycopods, and mosses in the understory. This forest developed under temperate and moist conditions during the middle Campanian-Maastrichtian.
- Published
- 2019
- Full Text
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27. Integrated bio- and cyclostratigraphy of Middle Triassic (Anisian) ramp deposits, NW Bulgaria
- Author
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Ajdanlijsky George, Strasser André, and Götz Annette E.
- Subjects
Sedimentary cycles ,palynology ,conodonts ,Triassic ,Western Balkanides ,NW Bulgaria ,Geology ,QE1-996.5 - Abstract
A cyclostratigraphic interpretation of peritidal to shallow-marine ramp deposits of the early Middle Triassic (Anisian) Opletnya Member exposed in outcrops along the Iskar River gorge, NW Bulgaria, is presented. Based on facies trends and bounding surfaces, depositional sequences of several orders can be identified. New biostratigraphic data provide a time frame of the studied succession with placement of the boundaries of the Anisian substages and show that the Aegean (early Anisian) substage lasted about 1.6 Myr. In the corresponding interval in the two studied sections, 80 elementary sequences are counted. Five elementary sequences compose a small-scale sequence. The prominent cyclic pattern of the Opletnya Member can thus be interpreted in terms of Milankovitch cyclicity: elementary sequences represent the precession (20-kyr) cycle and small-scale sequences the short eccentricity (100-kyr) cycle in the Milankovitch frequency band. Medium-scale sequences are defined based on lithology but only in two cases can be attributed to the long eccentricity cycle of 405 kyr. The transgressive-regressive facies trends within the sequences of all scales imply that they were controlled by sea-level changes, and that these were in tune with the climate changes induced by the orbital cycles. However, the complexity of facies and sedimentary structures seen in the Opletnya Member also implies that additional factors such as lateral migration of sediment bodies across the ramp were active. In addition, three major sequence boundaries have been identified in the studied sections, which can be correlated with the boundaries Ol4, An1, and An2 of the Tethyan realm.
- Published
- 2019
- Full Text
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28. A palynological study of an extinct Arctic ecosystem from the Palaeocene of Northern Alaska
- Author
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Daly, Robert James
- Subjects
560 ,Geology, Stratigraphic ,Geology ,Palynology - Abstract
Here is presented a high resolution vegetation model and ecological analysis of an extinct floodplain ecosystem based on the palynology of deposits of the Sagwon Bluffs, northeast Alaska. This fluvio – lacustrine succession of coal – bearing beds is of Late Palaeocene age and dominated by fine-grained sediment interspersed by coarse sandstones and conglomerates. Deposition occurred at a latitude of ~ 85° N, but owing to the Palaeocene greenhouse climate, mean annual temperatures as high as 6 - 7°C allowed temperate plant ecosystems to exist. The palynological dataset has been analysed here using ‘Correspondence Analysis’ (CA) and ‘Fuzzy c-Means Cluster analysis’ (FCM), allowing assessment of proposed ecological groups. Geochemical analysis has been incorporated using ‘Canonical Correspondence Analysis’ (CCA), demonstrating affiliations of certain taxa to chemical signatures of associated sediments. These techniques collectively reveal a gymnosperm – dominated floodplain forest with a substantial angiosperm, fern and bryophyte component analogous to modern wooded bogs and riparian swamp forests. Principal taxa of late seral development include Metasequoia, Taxodium, Sequoia and Nyssa, representing the dominant component of such a forest. Mid seral floras were characterised by coniferous gymnosperm and broad-leaved angiosperm co-dominance, incorporating Corylus, Alnus, Castanea, Ginkgo and a diversity of Pteridaceous, Polypodiaceous, Osmundaceous and Schizaceaen ferns. Variably high abundances of Sphagnum-type bryophyte spores suggest extensive peat-forming mires. The inconsistencies of the ecological structure displayed in the palynological assemblage suggest a dynamic floodplain, however, affected by a changing hydrological and climatic regime. Climate cooling is considered to have affected the floras concurrent with an increasingly wet floodplain prior to a hypothesised period of mountain building to the south.
- Published
- 2010
29. Evolution of Lake Paleolotos (the south of the Russian Far East) in the Middle Pleistocene
- Author
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N. I. Belyanina, P.S. Belyanin, and Yu.A. Mikishin
- Subjects
Palynology ,Marine Isotope Stage 11 ,biology ,Pleistocene ,Celtis ,Physical geography ,Vegetation ,biology.organism_classification ,Far East ,Alder ,Bay ,Geology ,Earth-Surface Processes - Abstract
This paper presents recently obtained palebotanical data regarding the evolution of Lake Paleolotos in the Middle Pleistocene. Its evolution was more complicated than the development of the adjacent lakes in the coast of Peter the Great Bay (the Sea of Japan). The Middle Pleistocene lacustrine sediments accumulated in the downstream of the Tumannaya River (the most southwestern area of Primorye, Russia Far East) were studied using diatom and pollen analytical methods. We found that the Lake Paleolotos arose during Marine Isotope Stage 11 (MIS 11) and disappeared during MIS 6. For more than half of its existence (MIS 11–8), it was a freshwater oligotrophic basin with a depth of at least 20 m, with clear waters and poor organic matter content. The lake occupied most of the modern accumulative plain on the left bank of the Tumannaya River, reaching a size of at least 10–12 km across. During MIS 7–6 Lake Paleolotos turned into a shallow-water basin (its depth most likely did not exceed 1–3 m) of a eutrophic type with turbid waters rich in organic matter. Palynological data suggest that during MIS 11, 9 and 7 the area adjacent to the Lake was covered with coniferous/broad-leaved forests with presence of some thermophilic plants of North China and North Korea Flora (Castanea, Celtis, Magnolia, Tsuga and Cupressaceae). This indicates that vegetation zones were displaced by about 500–700 km to the north relative to their present position. During periods of cooling they were replaced by coniferous/small-leaved forests with the participation of shrub species of birch and alder (MIS 10) and coniferous/small-leaved forests consisted of pine, birch, and spruce with the participation of elm and oak (MIS 8 and 6).
- Published
- 2023
30. PALYNOLOGY AND CHEMOSTRATIGRAPHY OF MIDDLE TRIASSIC SUCCESSIONS IN NORTHERN SWITZERLAND (WEIACH, BENKEN, LEUGGERN) AND SOUTHERN GERMANY (WEIZEN, FREUDENSTADT)
- Author
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PETER A. HOCHULI, ELKE SCHNEEBELI-HERMANN, PETER BRACK, KARL RAMSEYER, and DANIEL REBETEZ
- Subjects
Palynology ,Palynofacies ,Germanic Basin ,Middle Triassic ,Anisian ,Ladinian. ,Geology ,QE1-996.5 ,Paleontology ,QE701-760 - Abstract
New Anisian to Ladinian palynology, palynofacies and stable carbon isotope records are reported for the Middle Triassic from deep Swiss wells (Weiach, Benken, Leuggern), well B3/13 (Weizen, S-Germany) and the type area of the Freudenstadt Formation in southern Germany. A wide spectrum of moderately to well-preserved palynomorphs represent a high Middle Triassic plant diversity. Based on the distribution of diverse spore-pollen assemblages five Anisian Palynozones (A–E) and two Ladinian ones (F, G) are differentiated. Throughout these Palynozones the occurrence of spores and pollen, assigned to plant groups so far known only from the Palaeozoic, shed a new light on the evolution of plant assemblages during the Triassic. The comparison of Palynozones A–G with palynostratigraphic schemes from the central part of the Germanic Basin and from the Tethyan realm demonstrate the regional variability of marker species ranges – especially for the Anisian. n agreement with the lithological record, two prominent transgressive events (Lower Muschelkalk, Upper Muschelkalk) are indicated by increased abundances of marine particulate organic matter in palynofacies data. Marginal marine influence is documented at the base of the studied interval, comprising the Buntsandstein and the base of the Lower Muschelkalk. Carbonate carbon isotopes data show a negative shift at the boundary between lower and middle Muschelkalk. Coincidently, a prominent change in relative abundances of climate-sensitive plant groups (e.g. Triadispora spp. vs. Pteridophytes) indicate a change to relatively dryer climatic conditions during the middle Muschelkalk.
- Published
- 2020
- Full Text
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31. UNA SEQUENZA PALINOLOGICA DI ETA' RUSCINIANA NEI SEDIMENTI LACUSTRI BASALI DEL BACINO DI AULLA-OLIVOLA (VAL DI MAGRA)
- Author
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REMO BERTOLDI
- Subjects
Palynology ,Ruscinian ,Villafranchian ,Val di Magra ,Northern Italy. ,Geology ,QE1-996.5 ,Paleontology ,QE701-760 - Abstract
Palynological investigations were carried out on the basal sediments of the Aulla-Olivola basin, precisely on the Aulla lacustrine deposit, which underlies by about 200 m, both stratigraphically and geometricall", the Olivola village, known for its famous Villafranchian fauna. This research has revealed; • a very rich palynoflora and a long, complex, vegetational succession. dominated by arboreal formations, with high abundance of exotic taxa, including also tropical-subtropical elements; • a climatic Sequence characterized by oscillations reflecting seasonality, especially in pluvial regime. A most evident climatic change occurs in the middle of the sequence. Moreover, the palynological sequence made it possible: • to assign the examined sequence to the Pliocene, because of the abundance of "Tertiary" elements (Taxodium-type, Sciadopitys, Sequoia-type, Nyssa, Palmae, etc.); • to-ascertain the rather archaic character of the Aulla pollenflora because of the significant occurrence Of pollen assemblages mainly confined to pre-Pliocene and early Pliocene (Symplocos, Sapotaceae, Clethraceae/Cyrillaceae-type, Magnolia-type, Sapindaceae- type, Sterculiaceae, cfr. Castanopsis, Tricolporopollenites sp. of archaic-type, etc.); • to compare the Aulla pollenflora with Other Pliocene pollen microfloras from Italy and Other areas and to evidence affinities and differences. From these comparisons it appears clearly that the Aulla lacustrine episode represents the most ancient continental Pliocene deposit discovered in Italy by means of pollen analyses so far. In fact, the palynological and climatic features indicate that the pollen sequence of Aulla is certainly older than the establishement of glacial/interglacial climatic cycles in the Northern Hemisphere (—2,5 Ma). Also the Villafranca d'Asti deposit (Early Villafranchian in age) is older than 2,5 Ma on the base of the paleomagnetic data. But the pollen floras of Villafranca d'Asti (Fornace R.D.B.) do not include the pre- Pliocene and early Pliocene elements, which characterize the Aulla pollen records. All these considerations lead to Suggest an older chronostratigraphic collocation of the Aulla sequence, most likely in a pre-Vilafranchian interval, i.e., in the Ruscinian stage interval. The large floristic affinities with the pollen zones of the Brunssumian of the Netherlands, entirely included in the Ruscinian stage, and also the pollen affinities with the continental middle-Pliocene western-alpine deposits support the chronostratigraphical assignation of the Aulla deposit to a (probably late) Ruscinian phase. Finally, the pollen record of Aulla represents a particular uniform floristic biozone, which is named here "Macrian" phase, easily distinguished from the contiguous vegetational biozones. The results reported above allow to extend the chronostratigraphic scheme of the paleofloristic evolution in Northern-Central Italy during the Pliocene.
- Published
- 2020
32. The Early to Middle Triassic continental–marine transition of NW Bulgaria: sedimentology, palynology and sequence stratigraphy
- Author
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Ajdanlijsky George, Götz Annette E., and Strasser André
- Subjects
Lithofacies ,sedimentary cycles ,palynology ,continental–marine transition ,sequence stratigraphy ,Triassic ,NW Bulgaria ,Geology ,QE1-996.5 - Abstract
Sedimentary facies and cycles of the Triassic continental–marine transition of NW Bulgaria are documented in detail from reference sections along the Iskar river gorge between the villages of Tserovo and Opletnya. The depositional environments evolved from anastomosing and meandering river systems in the Petrohan Terrigenous Group to mixed fluvial and tidal settings in the Svidol Formation, and to peritidal and shallow-marine conditions in the Opletnya Member of the Mogila Formation. For the first time, the palynostratigraphic data presented here allow for dating the transitional interval and for the precise identification of a major sequence boundary between the Petrohan Terrigenous Group and the Svidol Formation (Iskar Carbonate Group). This boundary most probably corresponds to the major sequence boundary Ol4 occurring in the upper Olenekian of the Tethyan realm and thus enables interregional correlation. The identification of regionally traceable sequence boundaries based on biostratigraphic age control is a first step towards a more accurate stratigraphic correlation and palaeogeographic interpretation of the Early to early Middle Triassic in NW Bulgaria.
- Published
- 2018
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33. New climatic oscillations during MIS 11c in the record of the Skrzynka II site (Eastern Poland) based on palynological and isotope analysis
- Author
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Wojciech Drzewicki, Łukasz Pleśniak, Artur Górecki, Anna Hrynowiecka, Joanna Zalewska-Gałosz, and Marcin Żarski
- Subjects
palaeoclimatic record ,Palynology ,carbon isotope ,Holocene climatic optimum ,Ecological succession ,Paleontology ,Stage (stratigraphy) ,climate oscillation ,MIS 11c ,Interglacial ,Glacial period ,Weichselian glaciation ,palynology ,Holocene ,Geology ,Earth-Surface Processes - Abstract
Deposits of MIS 11c (Masovian Interglacial) are common in eastern Poland and therefore the area is considered as a Masovian palaeolakeland. In the Skrzynka II succession, MIS 11c lacustrine and MIS 10 lacustrine deposits of the early Liviecian Glaciation were found below beds representing the Weichselian Glaciation and the Holocene (1.35 m). The Mazovian Interglacial succession of the core as well as the base of the Liviecian Glaciation in depth interval 2.10–6.10 m were sampled for the purpose of palynological and isotope analyses. The main goal of the study was to determine a detailed record of climatic oscillations during MIS 11c. The palynological record of the Skrzynka II core contains nearly the entire MIS 11c succession, with an exception of the earliest protocratic stage. Both the previously described oscillation known from other European localities are present in the Skrzynka II record. Moreover, another major regressive oscillation, which was previously misinterpreted in two other Polish localities, was described in the late mesocratic phase. Yet another oscillation can be distinguished within the telocratic phase; it can be correlated with the ‘birch oscillation’ known so far only from Nowiny Żukowskie in Poland. Enhanced sampling resolution enabled also the description of several minor, local-scale climatic events or disturbances. Results of the isotope analysis correspond well with pollen data in the lower part of the succession, confirming a warming trend in the early interglacial and the cold character of the first regressive oscillation event. Since the second stage of the mesocratic phase, an unknown environmental disturbance occurred and δ13C(org) data are inconsistent with the pollen record until the end of the climatic optimum.
- Published
- 2022
34. Environmental changes recorded in the sequence of lake-peat bogs in the Eemian Interglacial and Vistulian on the basis of multi-proxy data
- Author
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Joanna Mirosław-Grabowska, Magdalena Radzikowska, Ryszard K. Borówka, Krzysztof Stefaniak, Renata Stachowicz-Rybka, Anna Hrynowiecka, Artur Sobczyk, and Joanna Sławińska
- Subjects
Palynology ,Eemian ,Peat ,Mire ,Geochemistry ,Fluvial ,Glacial period ,Structural basin ,Geology ,Earth-Surface Processes ,Water level - Abstract
We present the results of geochemical investigations, including stable isotope, of the Eemian (MIS 5e) and Vistulian (Weichselian, MIS 5a–d, MIS 3–4) sediments of the palaeolake horizons from Gorzow Wielkopolski site (NW Poland). Our analyzes comprised two profiles from different parts of lake basin, each approximately 11-m long. The deposits represent two cycles of lake accumulation (two limnic layers), each ended by peat deposition, separated by mineral fluvial deposits. The lower and upper limnic layers, despite several similar geochemical features, are records of two separate phases of the lake's functioning. The palynological data suggest that the mineral deposits separating them are not continuous succession, but contain a stratigraphic hiatus. We characterized six geochemical zones (GZ), which correspond well with lithological features of deposits and climatic changes, and reflect the changing environmental conditions (redox conditions, variability and intensity of denudation, biological productivity, and fertility of the environment). In the first phase of lake's development, some influence of the surface material supply is visible, indicated by the increased content of lithophilous elements, (e.g. potassium), as well as closely correlated with them copper and zinc. Slow accumulation of carbonates dominated the limnic layers due to their abundant supply from the catchment area. The greatest variations of isotopic values of carbonates occur in the bottom and at the top of the stratigraphic profile and are related to the changing environmental conditions in the lake's basin (water level and temperature variations). The differences in carbon and nitrogen isotope values suggest different sources of organic matter accumulated in the studied basin and varying trophy of the environment. The higher mercury content is related to the course of climate change and is the highest in cold periods. We identified five main phases of evolution of the palaeolake at Gorzow Wielkopolski site. The lake accumulation began during the final phase of the Wartanian (Late Saalian) Glaciation (MIS 6). Initially the palaeolake harmonically developed and reached its maximum depth (Early and Middle Eemian, MIS 5e). Next the palaeolake became shallower and transformed into the peatbog (Late Eemian, MIS 5e). In the Early Vistulian period (or Early Weichselian, MIS 5a–d), the lake re-existed, initially as a flow-through lake. Finally in middle Vistulian (or Middle Weichselian – Pleniglacial, MIS 3–4), the palaeolake declined and mire developed.
- Published
- 2022
35. Carbon Isotopic Signature and Organic Matter Composition of Cenomanian High-Latitude Paleosols of Southern Patagonia
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Augusto Nicolás Varela, María Sol Raigemborn, Patricio Emmanuel Santamarina, Sabrina Lizzoli, Thierry Adatte, and Ulrich Heimhofer
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carbon isotopes ,carbon cycle ,terrestrial deposits ,palynology ,mid-cretaceous ,Southern Gondwana ,Geology ,QE1-996.5 - Abstract
The Cenomanian Mata Amarilla Formation (MAF) in southern Patagonia (~55° S paleolatitude, Austral-Magallanes Basin, Argentina) is composed mainly of stacked fluvial deposits with intercalated paleosols, which document Cenomanian environments at high-paleolatitudes in the Southern Hemisphere. We performed a multiproxy study of the paleosols and sediments of the MAF in order to (1) understand the composition of the soil- and sediment-derived organic matter (OM), (2) apply carbon isotope stratigraphy as a tool to correlate patterns obtained from the MAF with existing marine and non-marine δ13Corg records worldwide, and (3) investigate the relationship between variations in spore-pollen assemblages of the MAF and the climatic conditions prevailing in the Cenomanian Southern Hemisphere. An integrated dataset was generated, including total organic carbon content, Rock-Eval pyrolysis data, stable isotope (δ13Corg) composition, and palynological data, combined with published paleosol-derived mean annual temperatures and mean annual precipitations. The results indicated that the OM preserved in the MAF paleosols allowed its use as a chemostratigraphic tool. The MAF δ13Corg curve showed the rather stable pattern characteristic for the Early to Late Cenomanian interval. The absence of the major positive carbon isotope excursion associated with oceanic anoxic event 2 provided an upper limit for the stratigraphic range of the MAF. The palynological data suggested the development of fern prairies during warmer and moister periods at the expense of the background gymnosperm-dominated forests. Overall, the multiproxy record provided new insights into the long-term environmental conditions during the Cenomanian in the high latitudes of the Southern Hemisphere.
- Published
- 2021
- Full Text
- View/download PDF
36. Age and conditions of the formation of the buried soils in the Stajki section by palynological studies
- Author
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Yadviga K. Yelovicheva
- Subjects
palynology ,holocene ,vegetation ,buried soils ,climate ,holocene interglaciation ,Geography (General) ,G1-922 ,Geology ,QE1-996.5 - Abstract
In the article are set forth materials of the palynological researches of the soil sediments in the section et the vil. Stajki (Mogilev Podniepr, Belarus), the age of which is dated Holocene interglacial (isotopic stage 1). Characterized spectra clearing composition 1 (phase SA-1, 2, 3) and 2 (early Holocene: PB-1, BO-2; Middle Holocene: AT-1, 2, 3; Late Holocene: SB-1, 2; SA-1, 2, 3), the character of the vegetation of paleolandscapes (pine forests with birch → pine forests with meso- and thermophilic breeds → broad-leaved forest (linden, oak-elm and then hornbeam and hornbeam forests, alder) → spruce and pine forests with meso- and thermophilic breeds → pine with spruce and birch), especially palynoflora (rare-seldom in the Holocene optimum Abies alba, Larix, Nymphaea alba, Salvinia natans), dynamics of palaeolake (the riverbed in the Late Glacial and early Holocene – 13 900–10 000 y. a., overgrown of riverbed in predoptimum time – 8400–8800 y. a., marsh regime in the Holocene optimum – 8000–5300 y. a., renewal of river flow from the end of optimum (AT-3-d) to the beginning SB – 4700–5300 y. a. in the steady slow mode, and in a more dynamic – in SB-1, SB-2 – 1600– 4700 y. a., soil development in the SA-3 (1600 y. a. – present)) and paleoclimate (cool and dry, then moderately-warm and dry in predoptimum time, warm and humid in the Holocene optimum, moderately-warm and humid, the change of moderately-warm and dry in postoptimum time) of the selected stages.
- Published
- 2017
37. Late Devonian–Early Carboniferous palynology of the CSDP-2 Borehole in the southern Yellow Sea, China
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John E. A. Marshall, Huinan Lu, Hong-He Xu, Xingwei Guo, Huiping Peng, Lai-Xing Cai, Shu Ouyang, Xunhua Zhang, Feng Liu, and Ning Yang
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Palynology ,010506 paleontology ,Outcrop ,Stratigraphy ,Borehole ,Paleontology ,010502 geochemistry & geophysics ,01 natural sciences ,Tournaisian ,Carboniferous ,Late Devonian extinction ,China ,Ecology, Evolution, Behavior and Systematics ,Geology ,0105 earth and related environmental sciences - Abstract
Late Devonian–Early Carboniferous spores recovered from the depths of 2140 m to 2031.3 m in the CSDP-2 Borehole in the southern Yellow Sea are systematically documented to characterize palynological associations for the stratigraphic correlation. The taxonomic study identifies 96 species belonging to 48 genera, including a re-examination of 33 previously described and indeterminate species. Three palynological associations are established for the Wutong Formation in the CSDP-2 Borehole. In ascending order, these are the late Famennian Aneurospora asthenolabrata–Geminospora lemurata (AL) Association from the proposed Guanshan Member, the latest Famennian Cymbosporites circinatus–Asperispora acuta (CA) Association from the lower part of the proposed Leigutai Member, and the Tournaisian Auroraspora macra–Lophozonotriletes involutus (MI) Association of the upper part of the latter member. The AL and CA associations are correlated with the palynological assemblages in the Guanshan Member, and those in the lower to middle parts of the Leigutai Member of the Wutong Formation that outcrops in the suburbs of Nanjing and southern Jiangsu. The MI Association is similar to those derived from the uppermost beds of the subsurface Wutong Formation and is dated as early Tournaisian.
- Published
- 2022
38. Peat Accumulation and Early Carboniferous Environments of the Kizel Coal Basin, the Urals, Russia
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Serge V. Naugolnykh
- Subjects
Palynology ,Peat ,business.industry ,Lithology ,Coal basin ,Carboniferous ,Paleobotany ,Geochemistry ,Geology ,Coal ,business ,Palaeogeography - Published
- 2022
39. Biostratigraphic correlation of the western and eastern margins of the Labrador-Baffin Seaway and implications for the regional geology
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Henrik Nøhr-Hansen, Graham L. Williams, and Robert .A. Fensome
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Baffin Margin ,Labrador Margin ,offshore West Greenland Cretaceous ,Cenozoic ,biostratigraphy ,palynology ,dinocysts ,palaeenvironments ,Geology ,QE1-996.5 ,Geophysics. Cosmic physics ,QC801-809 - Abstract
New analyses of the palynological assemblages in 13 offshore wells on the Canadian margin and six on the West Greenland Margin, in conjunction with onshore data, have led to a new biostratigraphic framework for the Cretaceous–Cenozoic strata of the Labrador Sea – Davis Strait – Baffin Bay (Labrador–Baffin Seaway) region and the first broad biostratigraphic correlation of the Canadian and Greenland margins. This framework is based on 167 last occurrences and 18 local/regional peak/common-occurrence events for dinocysts, miospores, fungal spores and Azolla. Detailed biostratigraphic evidence has confirmed the following hiatuses: pre-Aptian in the Hopedale Basin; pre-Albian in the Saglek Basin; Albian–Turonian in some wells of the Hopedale Basin; Turonian–Santonian/Campanian in some areas; pre-Campanian and late Campanian – Thanetian on the Greenland Margin; late Maastrichtian and Danian in some wells of the Hopedale Basin and in the Saglek Basin; Selandian in part of the Hopedale Basin, in all the Saglek Basin wells and in two wells on the West Greenland Margin; late Ypresian and/or Lutetian on both sides; Oligocene to middle Miocene of considerable variability on both margins, with all of the Oligocene and the lower Miocene missing in all the West Greenland Margin wells; and middle to late Miocene on the western side. On the Canadian margin, the hiatuses can be partially matched with the five previously recognised regional unconformities; on the Greenland margin, however, the relationship to the five unconformities is more tenuous. Palynomorph assemblages show that most Aptian to Albian sediments were deposited in generally non-marine to marginal marine settings, interrupted by a short-lived shallow marine episode in the Aptian. A marine transgression started in the Cenomanian–Turonian and led to the most open-marine, oceanic conditions in the Campanian–Lutetian; shallowing probably started in the late Lutetian and continued into the Rupelian, when inner neritic and marginal marine palaeoenvironments predominated. Throughout the rest of the Cenozoic, inner neritic palaeoenvironments alternated with marginal marine conditions on the margins of the Labrador–Baffin Seaway. These observations broadly reflect the tectonic evolution of the seaway, with rift conditions prevailing from Aptian to Danian times, followed by drift through much of the Paleocene and Eocene, and post-drift from Oligocene to the present. Dinocysts indicate that climatic conditions in the Labrador–Baffin Seaway region were relatively temperate in the Cretaceous, but varied dramatically through the Cenozoic. The Danian was a time of increasingly warmer climate, a thermal maximum being reached around the Paleocene–Eocene boundary reflecting the global thermal event at this time. Warm to hot conditions prevailed throughout the Ypresian, but the climate began to cool in the Lutetian, a trend that accelerated through the Priabonian and Rupelian. Throughout the Neogene, temperatures generally declined, culminating in the Quaternary.
- Published
- 2016
40. Vegetation and climate changes in the forest of Campinas, São Paulo State, Brazil, during the last 25,000 cal yr BP
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Adriana Mercedes Camejo Aviles, Fresia Ricardi-Branco, Marie-Pierre Ledru, and Luís Carlos Bernacci
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Quaternary ,palynology ,riparian forest ,late glacial ,Holocene ,Geology ,QE1-996.5 - Abstract
Abstract A paleoenvironmental reconstruction was performed in a Riparian Forest near Campinas to improve knowledge of paleoclimate and paleoenvironment in the State of São Paulo, Brazil. A sediment core of 182 cm depth was collected in a swamp located within a Cerrado/Seasonal Semi-deciduous ecotone forest. The chronological frame is given by eight radiocarbon dating methods. Pollen and stable isotope analyses (δ 13C and δ 15N) were performed all along the core. Modern pollen rain is based on five surface samples collected along the Riparian Forest. Results show a sequence of changes in vegetation and climate between 25 and 13 cal kyr before present (BP), and from 4 cal kyr BP to the present time, with a hiatus between 11 and 4 kyr cal BP. Drier climatic conditions characterized the late Pleistocene and early Holocene, although they had moisture peaks able to maintain an open forest. The Riparian Forest became fully installed from 4 cal kyr BP onward. Our results are in agreement with other regional studies and contribute to build a regional frame for past climatic conditions at the latitude of São Paulo.
- Published
- 2019
- Full Text
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41. The Searsville Lake Site (California, USA) as a candidate Global Boundary Stratotype Section and Point for the Anthropocene Series
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M Allison Stegner, Elizabeth A Hadly, Anthony D Barnosky, SeanPaul La Selle, Brian Sherrod, R Scott Anderson, Sergio A Redondo, Maria C Viteri, Karrie L Weaver, Andrew B Cundy, Pawel Gaca, Neil L Rose, Handong Yang, Sarah L Roberts, Irka Hajdas, Bryan A Black, and Trisha L Spanbauer
- Subjects
Global and Planetary Change ,GSSP ,Ecology ,plutonium ,Geology ,paleoecology ,Anthropocene ,cladocera ,elemental analyses ,geochemistry ,heavy metals ,ostracods ,palynology - Abstract
Cores from Searsville Lake within Stanford University’s Jasper Ridge Biological Preserve, California, USA, are examined to identify a potential GSSP for the Anthropocene: core JRBP2018-VC01B (944.5 cm-long) and tightly correlated JRBP2018-VC01A (852.5 cm-long). Spanning from 1900 CE ± 3 years to 2018 CE, a secure chronology resolved to the sub-annual level allows detailed exploration of the Holocene-Anthropocene transition. We identify the primary GSSP marker as first appearance of 239,240Pu (372–374 cm) in JRBP2018-VC01B and designate the GSSP depth as the distinct boundary between wet and dry season at 366 cm (6 cm above the first sample containing 239,240Pu) and corresponding to October-December 1948 CE. This is consistent with a lag of 1–2 years between ejection of 239,240Pu into the atmosphere and deposition. Auxiliary markers include: first appearance of 137Cs in 1958; late 20th-century decreases in δ15N; late 20th-century elevation in SCPs, Hg, Pb, and other heavy metals; and changes in abundance and presence of ostracod, algae, rotifer, and protozoan microfossils. Fossil pollen document anthropogenic landscape changes related to logging and agriculture. As part of a major university, the Searsville site has long been used for research and education, serves users locally to internationally, and is protected yet accessible for future studies and communication about the Anthropocene., The Anthropocene Review, 10 (1), ISSN:2053-0196, ISSN:2053-020X
- Published
- 2023
42. Palaeoenvironmental changes and their chronology during the latter half of MIS 5 on the south-eastern coast of the Gulf of Finland
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Nataliya S. Bolikhovskaya and Anatoly Molodkov
- Subjects
Palynology ,Marine isotope stage ,Paleontology ,Pleistocene ,Interglacial ,Period (geology) ,Climate change ,Weichselian glaciation ,Geology ,Earth-Surface Processes ,Chronology - Abstract
This paper presents an overview of the results obtained by collaborative use of integrative multidisciplinary investigation of a highly unique geological section discovered in the south-eastern part of the Gulf of Finland. The main aim of this study is to identify the Late Pleistocene palaeoenvironmental and palaeoclimatic changes in the study area during one of the most controversial periods in the Late Pleistocene history, which is the MIS 5. Our approach to achieving the goal is based on the investigation of feldspar-based infrared optically stimulated luminescence (IR-OSL) dated records of pollen-induced palaeoclimate and palaeoenvironmental proxies. Palynological analysis and IR-OSL dates of 29 samples for the first time produced a detailed, characterised and dated sequence of palynological zones M6 to M8 ranging from ca. 94 ka to ca. 70 ka and made it possible to determine the chronological sequence of climate changes in this interval. Representative pollen spectra from 69 samples provided convincing evidence of a warm interval of interglacial rank at least during the latter half of MIS 5. The data obtained in the present study from well-preserved deposits of the second half of MIS 5 provided a novel insight into the palaenvironmental conditions during this period. These results seem to contradict the widely held view according to which the last interglacial stage with the climate conditions similar or warmer than today corresponds to only a small part of marine isotope stage (MIS) 5 of the deep-sea stratigraphy, i.e. MISs 5e lasting ca. 11 ka, and the period from 100 ka to 80 ka is attributed to an Early Weichselian glaciation, which in Northern Eurasia reached its maximum at about 90 ka. However, the findings obtained during the present study are also convincingly confirmed by those of our previous long-term investigations of warm climate-related shell-bearing deposits of various origins from Northern Eurasia including climatically highly sensitive Eurasian Arctic palaeo-shelf area. These results indicated that the overwhelming majority of the warm climate-related dates (ca. 82%) is also concentrated in the latter half of MIS 5 in the time range between 110 ka and 70 ka.
- Published
- 2022
43. A palaeoenvironmental record of MIS 3 climate change in NE Poland—Sedimentary and geochemical evidence
- Author
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Tomasz Karasiewicz, Piotr Moska, Mark Demitroff, Magdalena Fiłoc, Joanna Rychel, Mirosława Kupryjanowicz, Barbara Woronko, and Aleksander Adamczyk
- Subjects
Palynology ,Marine isotope stage ,Sedimentary depositional environment ,Aggradation ,Geochemistry ,Fluvial ,Sediment ,Sedimentary rock ,Permafrost ,Geology ,Earth-Surface Processes - Abstract
In Eastern Europe Marine Isotope Stage (MIS) 3 represents a period characterised by severe climate change of very rapid onset, which is recorded in the regional sedimentary record. Hitherto this work, the geomorphic impact of these abrupt changes to NE Poland's 1st-order-stream valleys has been under-represented in studies. Here the combined results of lithological, geochemical, and palynological analyses—coupled with sediment OSL dating—demonstrate that MIS 3's earlier events (60–45 ka) mark an interval when contemporary dry valleys functioned as active stream corridors, places where deep fluvial incision had occurred. Prior to this MIS 3 fluvial activity there is an observed depositional hiatus encompassing sediments from MIS 5d to the oldest part of MIS 3. Valley-bottom sediment accumulation began ~44–40 ka, commencing at a time when shallow water reservoirs began to function. The resultant mineral infill is devoid of calcium carbonate and organic matter (OM). This sedimentation occurred under dry and cold climate conditions—i.e. under the influence of permafrost aggradation. The geochemical composition of the MIS 3 deposits indicates that environmental conditions are deteriorating. In effect, calcium carbonate was completely removed from the deposits, which resulted in the reduction of mobile elements (such as Na), removal of selected soil horizons, and an increased content of immobile elements—e.g. sedimentary Al, Rb, Ti. These processes are confirmed in the study sediments by magnetic susceptibility analysis. Here, in MIS 3 lake deposits, the presence of fissure structures filled with grey clay or fine sand is a common feature. Climatic changes during MIS 3's younger part were reflected in the slight increase of OM, which in turn increased the contribution of mobile, immobile, and trace elements. Most likely these change intervals represent more humid conditions during MIS 3. Sediment-trapping lakes within dry valley bottoms completely disappeared by ~30 ka.
- Published
- 2022
44. From the Neolithic to the present day: The impact of human presence on floristic diversity in the sandstone Northern Vosges (France)
- Author
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Gouriveau Emilie, Ruffaldi Pascale, Duchamp Loïc, Robin Vincent, Schnitzler Annik, Figus Cécile, and Walter-Simonnet Anne Véronique
- Subjects
palynology ,coprophilous fungi ,xrf geochemical analysis ,past floristic diversity ,human occupation ,vosges ,Geology ,QE1-996.5 - Abstract
The Northern Vosges and the Pays de Bitche (north-eastern France) are well-known regions for their rich recent industrial heritage. On the other hand, the ancient history of these regions is less well known and the relationships between human populations and their environments during ancient times is still largely unexplored. We carried out a multidisciplinary paleoenvironmental study on the site of the bog pond located below the ruins of the medieval castle of Waldeck in order to reconstruct the history of the vegetation in the region since 6600 cal. BP. Throughout the Holocene, the succession of forest vegetation (pine and hazelnut forests, reduced oak forest, beech forest, oak-beech forest) was largely dominated by pine. Human presence was tenuous during the Neolithic period, then well marked from the Bronze Age onwards with the introduction of crops and livestock crops in the catchment area. From the Middle Ages onwards, anthropic pressure increased dramatically with the building of Waldeck Castle in the thirteenth century, which led to a major opening of the area. The Modern period is characterized by a gradual return of the forest, with decreasing anthropogenic pressure. Over time, occupation phases were interspersed with abandonment phases during which human activities regressed or disappeared. Finally, the rarefaction analysis carried out on pollen data shows that human presence led to a gradual increase in plant diversity, which peaked in the Middle Ages, whereas the forest lost some of its resilience to human disturbance over time.
- Published
- 2021
- Full Text
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45. The unique devonian sections of Dniepro-Donetsk cavity. Kolaidyntsy parametric well 413. Article 2
- Author
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V. A. Ivanyshyn, L. P. Kononenko, O. L. Rakovska, S. V. Onufryshyn, and Z. G. Voloshyna
- Subjects
section ,core ,fauna ,devonian ,palynology ,stratigraphy ,Geology ,QE1-996.5 - Abstract
The article presents the results of comprehensive study materials drilling 413. When the actual depth of 5 104 m, it revealed the Anthropogenic, Quaternary, Neogene, Paleogene, Cretaceous, Jurassic, Triassic, Permian, Carbon and Devonian deposits which have a thickness of more than 3 600 m. The deposits of the Devonian attributed to Zadonsk-Yеlets (between salt). For stratigraphic and lithological features of this thickness in the Dnieper-Donets Basin is binary structure, which corresponds to two cycles of sedimentation. The lower part is represented by clay-carbonate rocks top – terrigenous. A terrigenous stratum in the north-western part of the basin is 800 m and increases to the southeast in the southern zone edge to 2 076 m in Peter’s well 1. Well 413 revealed only the upper strata of terrigenous capacity of over 3 600 m, so it is a unique cut. The porosity of the sand rocks is almost identical species at depths of 3 200–4 900 m, does not exceed 10 %. Wavy character of changes occurs only at a depth of 4 000–5 104 m.
- Published
- 2016
46. Snapshots of pre-glacial paleoenvironmental conditions along the Sabrina Coast, East Antarctica: New palynological and biomarker evidence
- Author
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Sophie Warny, Meghan Duffy, Amy Leventer, Catherine Smith, Gilles Escarguel, Rosemary A. Askin, Amelia E. Shevenell, Sarah J. Feakins, and Emily J. Tibbett
- Subjects
Palynology ,geography ,geography.geographical_feature_category ,Continental shelf ,Paleontology ,Antarctic ice sheet ,Glacier ,Oceanography ,Space and Planetary Science ,Paleoclimatology ,Glacial period ,Paleogene ,Cenozoic ,Geology - Abstract
The Aurora Subglacial Basin (ASB) catchment contains 3-5 m of sea-level equivalent ice volume that drains to the Sabrina Coast, East Antarctica via the Totten Glacier system. Observed thinning and retreat of Totten Glacier indicate regional sensitivity to oceanographic and atmospheric warming. Paleoclimate studies of climatically sensitive catchments are required to understand the evolution of the East Antarctic Ice Sheet (EAIS) and its outlet glacier systems. Recent seismic and sediment studies from the Sabrina Coast document the evolution of the EAIS in the ASB catchment, suggesting that the region has long been sensitive to climatic changes. This study presents new palynological and biomarker data from Sabrina Coast continental shelf sediments. Detailed palynological records were obtained from four short jumbo piston cores (JPC; NBP14-02 JPC-30, -31, -54 and -55), enabling reconstructions of regional vegetation and environments prior to and during Cenozoic EAIS development. The Sabrina Flora is dominated by angiosperms, with Gambierina spp. often exceeding 40% of the assemblage, and diverse Proteaceae, Battenipollis spp., Forcipites spp., Nothofagidites spp., fern, and conifer palynomorphs indicative of an open shrubby ecosystem. Excellent preservation and frequent occurrence of Gambierina spp. clusters suggest that a majority of the Sabrina Flora assemblage is penecontemporaneous with sedimentation; however, some uncertainties remain whether this sedimentation occurred in the Late Cretaceous or the Paleogene. Despite that uncertainty, high abundances of Gambierina spp. and Battenipollis spp., in combination with relatively low (
- Published
- 2022
47. Palynological evidence of Middle Pleistocene palaeoenvironmental changes from the ‘Buca dell’Onice’ flowstone (Alpi Apuane, Central Italy)
- Author
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Marco Massini, Leonardo Piccini, Adele Bertini, and Marianna Ricci
- Subjects
Palynology ,geography ,QE1-996.5 ,geography.geographical_feature_category ,Pleistocene ,Stratigraphy ,speleothems ,cave deposit ,Paleontology ,Geology ,Environmental Science (miscellaneous) ,karst ,Oceanography ,Karst ,medicine.disease_cause ,Mediterranean area ,Pollen ,pollen ,medicine ,late Quaternary - Abstract
Buca dell’Onice di Monte Girello is a small cave located in the Alpi Apuane (central Italy). It preserves an exceptionally thick flowstone deposited intermittently during the Middle Pleistocene. Two main depositional cycles, separated by a physical discontinuity, have been recognised and described. This discontinuity and the top surface of the flowstone attest to two main phases of interrupted growth related to palaeoenvironmental and palaeoclimate changes. Pilot palynological investigations support the existence of such changes. Despite the high number of barren pollen samples and the overall very low concentration of pollen grains per gram of sediment, palynology furnishes some interesting insights especially regarding floral composition, vegetation cover and local to regional climate. The pollen record also contributes to the definition of the stratigraphic distribution of taxa no longer growing in this area (i.e. Carya and Picea). According to the pollen assemblage characteristic of arboreal vegetation cover, the flowstone was deposited predominantly during humid phases under both warm and cool climate conditions (interglacials/interstadials and at the end of interglacials). The warm and cool phases correspond, respectively, to increases of mixed thermophilous forest taxa and montane arboreal taxa. On the other hand, the pollen record does not show the major expansion of open vegetation associated with the coldest and driest conditions, which apparently fall at the main middle discontinuity and at the top interruption of the flowstone. Previous data permit changes in precipitation to be identified as one of the major limiting factors for the growth of this flowstone, probably in a period including MISs 13‐10. The more significant lithological features of the flowstone as well as the vegetal and climate signatures suggest that its development principally represents a response to global events including teleconnections active between the Mediterranean and the Atlantic circulation, with minor contribution from local factors.
- Published
- 2022
48. Problems associated with the age determination of the oldest pottery yielding cultural layers at the Studenoe 1 site, Transbaikal (southern Siberia)
- Author
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Fumie Iizuka, Mikhail V. Konstantinov, Masami Izuho, and Ian Buvit
- Subjects
Palynology ,010506 paleontology ,Pleistocene ,010502 geochemistry & geophysics ,Permafrost ,01 natural sciences ,law.invention ,law ,Geochronology ,Physical geography ,Glacial period ,Pottery ,Radiocarbon dating ,Geology ,Holocene ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
s Two opinions exist regarding the appearance of the oldest pottery in the Transbaikal Region, Russia— (1) in the early Neolithic during the Holocene Atlantic optimum (6.5–5.5 ka Cal yr BP), or (2) during the Taymir Warm period of the Sartan Glacial (12.0–10.8 ka Cal yr BP)— both derived from the same archaeological component, Cultural Layer 9, at the Studenoe 1 Site. Here we scrutinized data related to the geochronology of early ceramic-yielding layers at Studenoe 1. Results show that the radiocarbon dates between 15,080 and 12,720 Cal yr BP contradict site stratigraphy which consists of vertically accreting overbank deposits and buried soil horizons that developed during periods of landscape stability. Palynological and stable-carbon isotope analyses also show inconsistencies with the calibrated radiocarbon dates. We do not yet know the reason for these anomalies, however, it may be that alpine glacier and permafrost thawing, and the subsequent supply of older carbon into the Chikoi River, ceased during cold periods, but accelerated during terminal Pleistocene and early Holocene warm periods, causing a systematic error of older radiocarbon dates.
- Published
- 2022
49. Remains of a subtropical humid forest in a Messinian evaporite-bearing succession at Govone, northwestern Italy – Preliminary results
- Author
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Edoardo Martinetto, Adele Bertini, Dimitra Mantzouka, Marcello Natalicchio, Gabriele Niccolini, and Johanna Kovar-Eder
- Subjects
Stratigraphy ,Pinales ,palaeobotany ,Messinian Salinity Crisis ,Fagaceae ,Juglandaceae ,Magnoliopsida ,Lauraceae ,Sapindaceae ,Betulaceae ,Platanaceae ,Symplocaceae ,Pentaphylacaceae ,Plantae ,Magnoliopsida (awaiting allocation) ,Saxifragales ,Rutaceae ,palynology ,fossil wood ,Ecology, Evolution, Behavior and Systematics ,Taxonomy ,Myricaceae ,Cupressaceae ,Paleontology ,Pinopsida ,Coniferales ,Geology ,Biodiversity ,Miocene ,Pinaceae ,palaeobotany, leaves, carpology, palynology, fossil wood, Messinian Salinity Crisis, Miocene ,carpology ,Proteales ,Sapindales ,Tracheophyta ,Laurales ,Altingiaceae ,Fagales ,leaves ,Ericales - Abstract
The first results of a multidisciplinary study on the Messinian evaporitic interval of the Govone section (northwestern Italy), subdivided into several sedimentary cycles, are reported here. Primary sulphate evaporites and intercalated shaly deposits, which formed during the Messinian Salinity Crisis, contain well-preserved and taxonomically determinable terrestrial plant remains. Palynomorphs are present continuously all along the analysed succession and among them, pollen is especially abundant and diverse. Additionally, a few fragments of silicified wood (which are rare in the studied area) occurred in layers rich in phytodebris, but their analysis showed poor preservation of anatomy. Carpological remains are not abundant and are strongly altered by diagenesis. Compressed conifer shoots and angiosperm leaves are well-preserved in several layers, one of which yielded a particularly diverse assemblage. The various plant records have been integrated to obtain an initial general idea on the floristic composition of the assemblages and the palaeoenvironment. We hypothesize that a subtropical humid forest may have surrounded the basin, not only during the deposition of shale deposits, but also during the formation of gypsum, generally considered a product of arid climate. Despite the low-resolution sampling strategy for macrofossils, the identification of several relevant plant taxa (Engelhardia orsbergensis, Eurya stigmosa, Symplocos casparyi, Taiwania sp.), seems to indicate that the Govone section could provide an interesting glimpse into the composition of the palaeoflora of northern Italy during the deposition of the Messinian evaporites.
- Published
- 2022
50. Environmental conditions and the emergence of ceramics in the Late Pleistocene-Early Holocene at the Krasnaya Gorka site in the Transbaikal region, Southern Siberia
- Author
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Daigo Natsuki, M. S. Lyaschevskaya, Shizuo Onuki, Hiroyuki Sato, Natalia Tsydenova, Dai Kunikita, and V. B. Bazarova
- Subjects
Palynology ,010506 paleontology ,Pleistocene ,Context (language use) ,010502 geochemistry & geophysics ,01 natural sciences ,Allerød oscillation ,law.invention ,Paleontology ,law ,Younger Dryas ,Stadial ,Radiocarbon dating ,Geology ,Holocene ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
New investigations of the Krasnaya Gorka site suggest the emergence of pottery in the Late Pleistocene-Early Holocene in the Transbaikal region. Several new AMS dates obtained for the early ceramic cultural layer 2 indicate an age between 13900-10500 cal BP. The results of palynological studies of the Krasnaya Gorka deposits are given in the paper for the first time, and the Late Pleistocene-Holocene environmental changes were reconstructed. Pollen data obtained from the Krasnaya Gorka profile showed cold and dry Late Pleistocene environmental conditions. The regional climate became milder and more humid around 13900–12700 cal BP, which corresponds to the Allerod interstadial thus corroborating the radiocarbon age results. The warmest interval of the Late Pleistocene occurred around 13500 cal BP. Between 12700 and 11800 cal BP, cooling probably corresponds to the cold and dry event of the Younger Dryas. There is some stratigraphical in deposits of the Krasnaya Gorka archeological site. The deposits forming in the early Holocene and beginning of the middle Holocene most likely were removed by erosion. Warming and increased humidity occurred in middle of the late Holocene (2700-1800 cal BP). During the late Holocene, the climate was unstable. Beginning 400 cal BP, the vegetation of the region acquired its modern appearance. Some published materials concerning reconstructions of paleoclimate in the region of Ust’-Karenga XII, Studenoe I, and Ust’-Menza I are considered in the context of general characteristics of the region. Therefore, both palynological reconstructions and radiocarbon dates place the earliest ceramics from Krasnaya Gorka within the final stage of the Late Pleistocene – Early Holocene between 13900-10500 cal BP.
- Published
- 2022
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