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Henk Brinkhuis - One of the best experts on this subject based on the ideXlab platform.
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Southern high-latitude terrestrial climate change during the Palaeocene-Eocene derived from a marine pollen record (ODP Site 1172, East Tasman Plateau)
Climate of the Past, 2014Co-Authors: Lineth Contreras, Appy Sluijs, Peter K Bijl, Jörg Pross, R. B. O'hara, J. I. Raine, Henk BrinkhuisAbstract:Abstract. Reconstructing the early Palaeogene climate dynamics of terrestrial settings in the high southern latitudes is important to assess the role of high-latitude physical and biogeochemical processes in the global climate system. However, whereas a number of high-quality Palaeogene climate records has become available for the marine realm of the high southern latitudes over the recent past, the long-term evolution of coeval terrestrial climates and ecosystems is yet poorly known. We here explore the climate and vegetation dynamics on Tasmania from the middle Palaeocene to the early Eocene (60.7–54.2 Ma) based on a sporomorph record from Ocean Drilling Program (ODP) Site 1172 on the East Tasman Plateau. Our results show that three distinctly different vegetation types thrived on Tasmania under a high-precipitation regime during the middle Palaeocene to early Eocene, with each type representing different temperature conditions: (i) warm-temperate forests dominated by gymnosperms that were dominant during the middle and late Palaeocene (excluding the middle/late Palaeocene transition); (ii) cool-temperate forests dominated by southern beech (Nothofagus) and araucarians that transiently prevailed across the middle/late Palaeocene transition interval (~ 59.5 to ~ 59.0 Ma); and (iii) paratropical forests rich in ferns that were established during and in the wake of the Palaeocene–Eocene Thermal Maximum (PETM). The transient establishment of cool-temperate forests lacking any frost-sensitive elements (i.e. palms and cycads) across the middle/late Palaeocene transition interval indicates markedly cooler conditions, with the occurrence of frosts in winter, on Tasmania during that time. The integration of our sporomorph data with previously published TEX86-based sea-surface temperatures from ODP Site 1172 documents that the vegetation dynamics on Tasmania were closely linked with the temperature evolution in the Tasman sector of the Southwest Pacific region. Moreover, the comparison of our season-specific climate estimates for the sporomorph assemblages from ODP Site 1172 with the TEX86L- and TEX86H-based temperature data suggests a warm bias of both calibrations for the early Palaeogene of the high southern latitudes.
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a magneto and chemostratigraphically calibrated dinoflagellate cyst zonation of the early palaeogene south pacific ocean
Earth-Science Reviews, 2013Co-Authors: Peter K Bijl, Appy Sluijs, Henk BrinkhuisAbstract:Abstract Investigation of the early Palaeogene palaeoecological and palaeoclimatological evolution of the Polar Regions is hindered by the absence of calcite microfossils in sedimentary archives, which are conventionally the main dating tool. To overcome this problem, we have generated large datasets of organic dinoflagellate cyst (dinocyst) assemblages from Southern Ocean shelf sediments over the past decade, and we here calibrate these to the Geomagnetic Polarity Time Scale (GPTS) using magnetostratigraphy and stable isotope stratigraphy. This now for the first time allows a high-resolution Southern Pacific Ocean dinocyst zonation for the late Palaeocene to late Eocene (58–36 million years ago; Ma). We compile published dinocyst chronologies from Ocean Drilling Program (ODP) Hole 1171D on the South Tasman Rise, Hole 1172A/D on the East Tasman Plateau and Integrated Ocean Drilling Program (IODP) Hole U1356A on the Wilkes Land margin. Correlation to dinocyst zonations from New Zealand lead to revisions of the magnetostratigraphic age model at Holes 1171D and 1172A/D. Stable carbon and oxygen isotope records reveal the stratigraphic location of the Palaeocene–Eocene Thermal Maximum (~ 56 Ma) and the Middle Eocene Climatic Optimum (~ 40 Ma), respectively. The resulting zonation consists of thirteen dinocyst zones, calibrated to the Geomagnetic Polarity Time Scale (GPTS) of Vandenberghe et al. (2012) , which can likely be applied to the entire Southern Ocean. Finally, we apply the revised stratigraphy to all published TEX86 data, a biomarker-based proxy for sea surface temperature (SST), from ODP Site 1172 to assess long-term climate evolution. This shows that Southwest Pacific SST trends mimic the global compilation of benthic foraminiferal oxygen isotopes even better than previously appreciated.
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subtropical arctic ocean temperatures during the Palaeocene eocene thermal maximum
Nature, 2006Co-Authors: Appy Sluijs, Henk Brinkhuis, Stefan Schouten, Mark Pagani, Martijn Woltering, Jaap Sinninghe S Damste, Gerald R Dickens, Matthew Huber, Gertjan Reichart, Ruediger SteinAbstract:The Palaeocene/Eocene thermal maximum, approximately 55 million years ago, was a brief period of widespread, extreme climatic warming, that was associated with massive atmospheric greenhouse gas input. Although aspects of the resulting environmental changes are well documented at low latitudes, no data were available to quantify simultaneous changes in the Arctic region. Here we identify the Palaeocene/Eocene thermal maximum in a marine sedimentary sequence obtained during the Arctic Coring Expedition. We show that sea surface temperatures near the North Pole increased from 18 degrees C to over 23 degrees C during this event. Such warm values imply the absence of ice and thus exclude the influence of ice-albedo feedbacks on this Arctic warming. At the same time, sea level rose while anoxic and euxinic conditions developed in the ocean's bottom waters and photic zone, respectively. Increasing temperature and sea level match expectations based on palaeoclimate model simulations, but the absolute polar temperatures that we derive before, during and after the event are more than 10 degrees C warmer than those model-predicted. This suggests that higher-than-modern greenhouse gas concentrations must have operated in conjunction with other feedback mechanisms--perhaps polar stratospheric clouds or hurricane-induced ocean mixing--to amplify early Palaeogene polar temperatures.
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late Palaeocene early eocene dinoflagellate cysts from the turgay strait kazakhstan correlations across ancient seaways
Palaeogeography Palaeoclimatology Palaeoecology, 2001Co-Authors: Henk Brinkhuis, Alina I. Iakovleva, Carla CavagnettoAbstract:Abstract The results of a quantitative palynological analysis, emphasizing organic-walled dinoflagellate cysts (dinocysts), of Palaeocene–Eocene deposits exposed in the Sokolovsky Quarry (Turgay Trough, Northern Kazakhstan) are presented here. Located in the ancient Turgay Strait, a former seaway presumed to have connected the Tethyan and Boreal oceans and seas in the early Palaeogene, the Sokolovsky Quarry outcrop occupies a key position for the analysis of connections between these realms. In general, the dinocyst succession of Sokolovsky closely resembles coeval Arctic Ocean–North Sea Basin counterparts; only in one interval endemic and/or possibly Tethyan species co-occur. The successive dinocyst assemblages allow recognition of the Late Palaeocene–Early Eocene P5a, P5b, P6a, P6b and E2 zones established in the North Sea Basin. The succession is interpreted to represent parts of several third-order sea level cycles correlative with those recognised in the North Sea Basin. Detailed comparison with similar studies from southeastern England allows the recognition of (parts of) third order cycles Thanetian-1 (Tht-1), 2, 4, 5, and Ypresian (Ypr)-3. In addition, two important stratigraphic gaps within the Palaeocene–Eocene succession are recognised, possibly reflecting times of sea level lowering. These gaps are inferred from (1) the absence of a complete P5b/P6a transition, (2) the absence of zone E1, and (3) (bio)sequence stratigraphy. Combined results indicate that the Turgay Strait flooded from the north between ∼57.8 and 57.1 Ma (cycles Tht-1 and 2, in part, with a minor missing section). During the ‘second’ phase of Turgay-flooding (∼56.4–55.3 Ma), evidence may be taken to indicate increased influence from the Tethyan Ocean and/or warmer conditions. Deposits reflecting the Late Palaeocene Thermal Maximum, associated with this interval, are present at Sokolovsky Quarry. This interval is marked by abundant Apectodinium spp., including A. augustum , and organic-rich layers. A third flooding is correlative to the London Clay transgression (from ∼54.5 Ma). From our study, no decisive evidence has become available that confirms that a connection between the Arctic and Tethyan oceans via the Turgay Strait in the early Palaeogene existed. Nevertheless, during intervals of major sea level fall, the Turgay Strait depression may be regarded to have been an important feature for migrating terrestrial biota. Four new wetzeliellioid taxa Apectodinium sp. A, Apectodinium sp. B, Wilsonidium ? sp. A and Wilsonidium ? sp. B are described from the Palaeocene part of the section.
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Late Palaeocene–Early Eocene dinoflagellate cysts from the Turgay Strait, Kazakhstan; correlations across ancient seaways
Palaeogeography Palaeoclimatology Palaeoecology, 2001Co-Authors: Alina I. Iakovleva, Henk Brinkhuis, Carla CavagnettoAbstract:Abstract The results of a quantitative palynological analysis, emphasizing organic-walled dinoflagellate cysts (dinocysts), of Palaeocene–Eocene deposits exposed in the Sokolovsky Quarry (Turgay Trough, Northern Kazakhstan) are presented here. Located in the ancient Turgay Strait, a former seaway presumed to have connected the Tethyan and Boreal oceans and seas in the early Palaeogene, the Sokolovsky Quarry outcrop occupies a key position for the analysis of connections between these realms. In general, the dinocyst succession of Sokolovsky closely resembles coeval Arctic Ocean–North Sea Basin counterparts; only in one interval endemic and/or possibly Tethyan species co-occur. The successive dinocyst assemblages allow recognition of the Late Palaeocene–Early Eocene P5a, P5b, P6a, P6b and E2 zones established in the North Sea Basin. The succession is interpreted to represent parts of several third-order sea level cycles correlative with those recognised in the North Sea Basin. Detailed comparison with similar studies from southeastern England allows the recognition of (parts of) third order cycles Thanetian-1 (Tht-1), 2, 4, 5, and Ypresian (Ypr)-3. In addition, two important stratigraphic gaps within the Palaeocene–Eocene succession are recognised, possibly reflecting times of sea level lowering. These gaps are inferred from (1) the absence of a complete P5b/P6a transition, (2) the absence of zone E1, and (3) (bio)sequence stratigraphy. Combined results indicate that the Turgay Strait flooded from the north between ∼57.8 and 57.1 Ma (cycles Tht-1 and 2, in part, with a minor missing section). During the ‘second’ phase of Turgay-flooding (∼56.4–55.3 Ma), evidence may be taken to indicate increased influence from the Tethyan Ocean and/or warmer conditions. Deposits reflecting the Late Palaeocene Thermal Maximum, associated with this interval, are present at Sokolovsky Quarry. This interval is marked by abundant Apectodinium spp., including A. augustum , and organic-rich layers. A third flooding is correlative to the London Clay transgression (from ∼54.5 Ma). From our study, no decisive evidence has become available that confirms that a connection between the Arctic and Tethyan oceans via the Turgay Strait in the early Palaeogene existed. Nevertheless, during intervals of major sea level fall, the Turgay Strait depression may be regarded to have been an important feature for migrating terrestrial biota. Four new wetzeliellioid taxa Apectodinium sp. A, Apectodinium sp. B, Wilsonidium ? sp. A and Wilsonidium ? sp. B are described from the Palaeocene part of the section.
Victoriano Pujalte - One of the best experts on this subject based on the ideXlab platform.
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The Palaeocene/Eocene boundary section at Zumaia (Basque-Cantabric Basin) revisited: new insights from high-resolution magnetic susceptibility and carbon isotope chemostratigraphy on organic matter (δ13Corg)
Terra Nova, 2012Co-Authors: Jean-yves Storme, Victoriano Pujalte, Juan Ignacio Baceta, Johann Schnyder, Paola Lacumin, Antonietta Di Matteo, Xavier Devleeschouwer, Geoffrey Cambier, Johan YansAbstract:The Zumaia section, the most complete and representative section of the early Palaeogene (hemi)-pelagic succession of the Pyrenees, is widely acknowledged as a key reference for the Palaeocene–Eocene boundary. New high-resolution δ13Corg of the Zumaia section (−23.8 to −28.8‰) confirms the position of the Carbon Isotope Excursion and enhances the distinction between the different steps of the CIE/PETM event. According to new magnetic susceptibility data and detailed cycle counting, the entire duration of the CIE/PETM in Zumaia is estimated in ∼168 ± 16 ka. Moreover, the investigation of palynofacies and low-field magnetic susceptibility reveal significant detrital influx during the interval. Several magnetic susceptibility phases and trends are recognised and are interpreted in terms of sea-level fluctuations before, during and after the PETM. Coupled with results from other sections, our data reveal the presence of an unconformity followed by an eustatic sea-level rise (TST) in the latest Palaeocene.
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closing the mid Palaeocene gap toward a complete astronomically tuned Palaeocene epoch and selandian and thanetian gssps at zumaia basque basin w pyrenees
Earth and Planetary Science Letters, 2007Co-Authors: Jaume Dinaresturell, Juan Ignacio Baceta, Gilen Bernaola, Xabier Orueetxebarria, Victoriano PujalteAbstract:Abstract An integrated magneto-, bio- and cyclostratigraphic framework is presented for the Mid-Palaeocene interval from the (hemi)pelagic sea-cliff section of Zumaia in the Basque basin. The new ∼ 55 m long studied section expands about 3.5 Myr and closes the gap between previously published integrated studies in the section. The occurrence of magnetochron C26n is now documented, and its duration (complemented also by data from the Ibaeta section), and that for chrons C26r and C25r is estimated by counting precession related lithologic couplets assigned to have 21-kyr duration (C25r = ∼ 1449 kyr, C26n = ∼ 231 kyr, C26r = ∼ 2877 kyr). Consequently, the Zumaia section now provides the first complete Palaeocene astronomically derived chronology, rendering this section a master reference section. Due to limitations in the orbital calculations and uncertainties in the radiometric dating method no robust tuning and absolute ages can be given for the moment. However, the FOs (First Occurrences) of key calcareous plankton species and the Mid Palaeocene Biotic Event (MPBE) are placed within the magnetostratigraphic and cyclostratigraphic template along the studied Mid-Palaeocene interval. In addition, the dataset provides the key elements for a proper settling of the Thanetian and Selandian Global Stratotype Section and Point (GSSPs), which is one of the primary objectives of the ICS (International Commission of Stratigraphy). We consider the base of chron C26n and the criteria associated to the lithostratigraphic change between the Danian Limestone Fm and the Itzurun marl Fm at Zumaia, as the respective delimiting points for the Thanetian and Selandian bases as recently agreed by the Paleocene Working Group of the International Subcommission of the Paleogene Stratigraphy of the ICS. Consequently, the duration of the Thanetian, Selandian and Danian component stages can be estimated at Zumaia to be about ∼ 3129 kyr, ∼ 2163 kyr and ∼ 4324 kyr respectively (see text for error considerations). However, the MPBE located 8 precession cycles below the base of C26n in correspondence to a short eccentricity maxima at Zumaia, could also serve as a guiding criteria to approximate or redefine the Thanetian base if this level demonstrated synchronous.
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Closing the Mid-Palaeocene gap: Toward a complete astronomically tuned Palaeocene Epoch and Selandian and Thanetian GSSPs at Zumaia (Basque Basin, W Pyrenees)
Earth and Planetary Science Letters, 2007Co-Authors: Jaume Dinarès-turell, Gilen Bernaola, Juan Ignacio Baceta, Xabier Orue-etxebarria, Victoriano PujalteAbstract:An integrated magneto-, bio- and cyclostratigraphic framework is presented for the Mid-Palaeocene interval from the (hemi) pelagic sea-cliff section of Zumaia in the Basque basin. The new ∼55 m long studied section expands about 3.5 Myr and closes the gap between previously published integrated studies in the section. The occurrence of magnetochron C26n is now documented, and its duration (complemented also by data from the Ibaeta section), and that for chrons C26r and C25r is estimated by counting precession related lithologic couplets assigned to have 21-kyr duration (C25r=∼1449 kyr, C26n=∼231 kyr, C26r=∼2877 kyr). Consequently, the Zumaia section now provides the first complete Palaeocene astronomically derived chronology, rendering this section a master reference section. Due to limitations in the orbital calculations and uncertainties in the radiometric dating method no robust tuning and absolute ages can be given for the moment. However, the FOs (First Occurrences) of key calcareous plankton species and the Mid Palaeocene Biotic Event (MPBE) are placed within the magnetostratigraphic and cyclostratigraphic template along the studied Mid-Palaeocene interval. In addition, the dataset provides the key elements for a proper settling of the Thanetian and Selandian Global Stratotype Section and Point (GSSPs), which is one of the primary objectives of the ICS (International Commission of Stratigraphy). We consider the base of chron C26n and the criteria associated to the lithostratigraphic change between the Danian Limestone Fm and the Itzurun marl Fm at Zumaia, as the respective delimiting points for the Thanetian and Selandian bases as recently agreed by the Paleocene Working Group of the International Subcommission of the Paleogene Stratigraphy of the ICS. Consequently, the duration of the Thanetian, Selandian and Danian component stages can be estimated at Zumaia to be about ∼3129 kyr, ∼2163 kyr and ∼4324 kyr respectively (see text for error considerations). However, the MPBE located 8 precession cycles below the base of C26n in correspondence to a short eccentricity maxima at Zumaia, could also serve as a guiding criteria to approximate or redefine the Thanetian base if this level demonstrated synchronous.Published450–4672.2. Laboratorio di paleomagnetismoJCR Journalreserve
Alina I. Iakovleva - One of the best experts on this subject based on the ideXlab platform.
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late Palaeocene early eocene dinoflagellate cysts from the turgay strait kazakhstan correlations across ancient seaways
Palaeogeography Palaeoclimatology Palaeoecology, 2001Co-Authors: Henk Brinkhuis, Alina I. Iakovleva, Carla CavagnettoAbstract:Abstract The results of a quantitative palynological analysis, emphasizing organic-walled dinoflagellate cysts (dinocysts), of Palaeocene–Eocene deposits exposed in the Sokolovsky Quarry (Turgay Trough, Northern Kazakhstan) are presented here. Located in the ancient Turgay Strait, a former seaway presumed to have connected the Tethyan and Boreal oceans and seas in the early Palaeogene, the Sokolovsky Quarry outcrop occupies a key position for the analysis of connections between these realms. In general, the dinocyst succession of Sokolovsky closely resembles coeval Arctic Ocean–North Sea Basin counterparts; only in one interval endemic and/or possibly Tethyan species co-occur. The successive dinocyst assemblages allow recognition of the Late Palaeocene–Early Eocene P5a, P5b, P6a, P6b and E2 zones established in the North Sea Basin. The succession is interpreted to represent parts of several third-order sea level cycles correlative with those recognised in the North Sea Basin. Detailed comparison with similar studies from southeastern England allows the recognition of (parts of) third order cycles Thanetian-1 (Tht-1), 2, 4, 5, and Ypresian (Ypr)-3. In addition, two important stratigraphic gaps within the Palaeocene–Eocene succession are recognised, possibly reflecting times of sea level lowering. These gaps are inferred from (1) the absence of a complete P5b/P6a transition, (2) the absence of zone E1, and (3) (bio)sequence stratigraphy. Combined results indicate that the Turgay Strait flooded from the north between ∼57.8 and 57.1 Ma (cycles Tht-1 and 2, in part, with a minor missing section). During the ‘second’ phase of Turgay-flooding (∼56.4–55.3 Ma), evidence may be taken to indicate increased influence from the Tethyan Ocean and/or warmer conditions. Deposits reflecting the Late Palaeocene Thermal Maximum, associated with this interval, are present at Sokolovsky Quarry. This interval is marked by abundant Apectodinium spp., including A. augustum , and organic-rich layers. A third flooding is correlative to the London Clay transgression (from ∼54.5 Ma). From our study, no decisive evidence has become available that confirms that a connection between the Arctic and Tethyan oceans via the Turgay Strait in the early Palaeogene existed. Nevertheless, during intervals of major sea level fall, the Turgay Strait depression may be regarded to have been an important feature for migrating terrestrial biota. Four new wetzeliellioid taxa Apectodinium sp. A, Apectodinium sp. B, Wilsonidium ? sp. A and Wilsonidium ? sp. B are described from the Palaeocene part of the section.
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Late Palaeocene–Early Eocene dinoflagellate cysts from the Turgay Strait, Kazakhstan; correlations across ancient seaways
Palaeogeography Palaeoclimatology Palaeoecology, 2001Co-Authors: Alina I. Iakovleva, Henk Brinkhuis, Carla CavagnettoAbstract:Abstract The results of a quantitative palynological analysis, emphasizing organic-walled dinoflagellate cysts (dinocysts), of Palaeocene–Eocene deposits exposed in the Sokolovsky Quarry (Turgay Trough, Northern Kazakhstan) are presented here. Located in the ancient Turgay Strait, a former seaway presumed to have connected the Tethyan and Boreal oceans and seas in the early Palaeogene, the Sokolovsky Quarry outcrop occupies a key position for the analysis of connections between these realms. In general, the dinocyst succession of Sokolovsky closely resembles coeval Arctic Ocean–North Sea Basin counterparts; only in one interval endemic and/or possibly Tethyan species co-occur. The successive dinocyst assemblages allow recognition of the Late Palaeocene–Early Eocene P5a, P5b, P6a, P6b and E2 zones established in the North Sea Basin. The succession is interpreted to represent parts of several third-order sea level cycles correlative with those recognised in the North Sea Basin. Detailed comparison with similar studies from southeastern England allows the recognition of (parts of) third order cycles Thanetian-1 (Tht-1), 2, 4, 5, and Ypresian (Ypr)-3. In addition, two important stratigraphic gaps within the Palaeocene–Eocene succession are recognised, possibly reflecting times of sea level lowering. These gaps are inferred from (1) the absence of a complete P5b/P6a transition, (2) the absence of zone E1, and (3) (bio)sequence stratigraphy. Combined results indicate that the Turgay Strait flooded from the north between ∼57.8 and 57.1 Ma (cycles Tht-1 and 2, in part, with a minor missing section). During the ‘second’ phase of Turgay-flooding (∼56.4–55.3 Ma), evidence may be taken to indicate increased influence from the Tethyan Ocean and/or warmer conditions. Deposits reflecting the Late Palaeocene Thermal Maximum, associated with this interval, are present at Sokolovsky Quarry. This interval is marked by abundant Apectodinium spp., including A. augustum , and organic-rich layers. A third flooding is correlative to the London Clay transgression (from ∼54.5 Ma). From our study, no decisive evidence has become available that confirms that a connection between the Arctic and Tethyan oceans via the Turgay Strait in the early Palaeogene existed. Nevertheless, during intervals of major sea level fall, the Turgay Strait depression may be regarded to have been an important feature for migrating terrestrial biota. Four new wetzeliellioid taxa Apectodinium sp. A, Apectodinium sp. B, Wilsonidium ? sp. A and Wilsonidium ? sp. B are described from the Palaeocene part of the section.
Carla Cavagnetto - One of the best experts on this subject based on the ideXlab platform.
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late Palaeocene early eocene dinoflagellate cysts from the turgay strait kazakhstan correlations across ancient seaways
Palaeogeography Palaeoclimatology Palaeoecology, 2001Co-Authors: Henk Brinkhuis, Alina I. Iakovleva, Carla CavagnettoAbstract:Abstract The results of a quantitative palynological analysis, emphasizing organic-walled dinoflagellate cysts (dinocysts), of Palaeocene–Eocene deposits exposed in the Sokolovsky Quarry (Turgay Trough, Northern Kazakhstan) are presented here. Located in the ancient Turgay Strait, a former seaway presumed to have connected the Tethyan and Boreal oceans and seas in the early Palaeogene, the Sokolovsky Quarry outcrop occupies a key position for the analysis of connections between these realms. In general, the dinocyst succession of Sokolovsky closely resembles coeval Arctic Ocean–North Sea Basin counterparts; only in one interval endemic and/or possibly Tethyan species co-occur. The successive dinocyst assemblages allow recognition of the Late Palaeocene–Early Eocene P5a, P5b, P6a, P6b and E2 zones established in the North Sea Basin. The succession is interpreted to represent parts of several third-order sea level cycles correlative with those recognised in the North Sea Basin. Detailed comparison with similar studies from southeastern England allows the recognition of (parts of) third order cycles Thanetian-1 (Tht-1), 2, 4, 5, and Ypresian (Ypr)-3. In addition, two important stratigraphic gaps within the Palaeocene–Eocene succession are recognised, possibly reflecting times of sea level lowering. These gaps are inferred from (1) the absence of a complete P5b/P6a transition, (2) the absence of zone E1, and (3) (bio)sequence stratigraphy. Combined results indicate that the Turgay Strait flooded from the north between ∼57.8 and 57.1 Ma (cycles Tht-1 and 2, in part, with a minor missing section). During the ‘second’ phase of Turgay-flooding (∼56.4–55.3 Ma), evidence may be taken to indicate increased influence from the Tethyan Ocean and/or warmer conditions. Deposits reflecting the Late Palaeocene Thermal Maximum, associated with this interval, are present at Sokolovsky Quarry. This interval is marked by abundant Apectodinium spp., including A. augustum , and organic-rich layers. A third flooding is correlative to the London Clay transgression (from ∼54.5 Ma). From our study, no decisive evidence has become available that confirms that a connection between the Arctic and Tethyan oceans via the Turgay Strait in the early Palaeogene existed. Nevertheless, during intervals of major sea level fall, the Turgay Strait depression may be regarded to have been an important feature for migrating terrestrial biota. Four new wetzeliellioid taxa Apectodinium sp. A, Apectodinium sp. B, Wilsonidium ? sp. A and Wilsonidium ? sp. B are described from the Palaeocene part of the section.
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Late Palaeocene–Early Eocene dinoflagellate cysts from the Turgay Strait, Kazakhstan; correlations across ancient seaways
Palaeogeography Palaeoclimatology Palaeoecology, 2001Co-Authors: Alina I. Iakovleva, Henk Brinkhuis, Carla CavagnettoAbstract:Abstract The results of a quantitative palynological analysis, emphasizing organic-walled dinoflagellate cysts (dinocysts), of Palaeocene–Eocene deposits exposed in the Sokolovsky Quarry (Turgay Trough, Northern Kazakhstan) are presented here. Located in the ancient Turgay Strait, a former seaway presumed to have connected the Tethyan and Boreal oceans and seas in the early Palaeogene, the Sokolovsky Quarry outcrop occupies a key position for the analysis of connections between these realms. In general, the dinocyst succession of Sokolovsky closely resembles coeval Arctic Ocean–North Sea Basin counterparts; only in one interval endemic and/or possibly Tethyan species co-occur. The successive dinocyst assemblages allow recognition of the Late Palaeocene–Early Eocene P5a, P5b, P6a, P6b and E2 zones established in the North Sea Basin. The succession is interpreted to represent parts of several third-order sea level cycles correlative with those recognised in the North Sea Basin. Detailed comparison with similar studies from southeastern England allows the recognition of (parts of) third order cycles Thanetian-1 (Tht-1), 2, 4, 5, and Ypresian (Ypr)-3. In addition, two important stratigraphic gaps within the Palaeocene–Eocene succession are recognised, possibly reflecting times of sea level lowering. These gaps are inferred from (1) the absence of a complete P5b/P6a transition, (2) the absence of zone E1, and (3) (bio)sequence stratigraphy. Combined results indicate that the Turgay Strait flooded from the north between ∼57.8 and 57.1 Ma (cycles Tht-1 and 2, in part, with a minor missing section). During the ‘second’ phase of Turgay-flooding (∼56.4–55.3 Ma), evidence may be taken to indicate increased influence from the Tethyan Ocean and/or warmer conditions. Deposits reflecting the Late Palaeocene Thermal Maximum, associated with this interval, are present at Sokolovsky Quarry. This interval is marked by abundant Apectodinium spp., including A. augustum , and organic-rich layers. A third flooding is correlative to the London Clay transgression (from ∼54.5 Ma). From our study, no decisive evidence has become available that confirms that a connection between the Arctic and Tethyan oceans via the Turgay Strait in the early Palaeogene existed. Nevertheless, during intervals of major sea level fall, the Turgay Strait depression may be regarded to have been an important feature for migrating terrestrial biota. Four new wetzeliellioid taxa Apectodinium sp. A, Apectodinium sp. B, Wilsonidium ? sp. A and Wilsonidium ? sp. B are described from the Palaeocene part of the section.
Juan Ignacio Baceta - One of the best experts on this subject based on the ideXlab platform.
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The Palaeocene/Eocene boundary section at Zumaia (Basque-Cantabric Basin) revisited: new insights from high-resolution magnetic susceptibility and carbon isotope chemostratigraphy on organic matter (δ13Corg)
Terra Nova, 2012Co-Authors: Jean-yves Storme, Victoriano Pujalte, Juan Ignacio Baceta, Johann Schnyder, Paola Lacumin, Antonietta Di Matteo, Xavier Devleeschouwer, Geoffrey Cambier, Johan YansAbstract:The Zumaia section, the most complete and representative section of the early Palaeogene (hemi)-pelagic succession of the Pyrenees, is widely acknowledged as a key reference for the Palaeocene–Eocene boundary. New high-resolution δ13Corg of the Zumaia section (−23.8 to −28.8‰) confirms the position of the Carbon Isotope Excursion and enhances the distinction between the different steps of the CIE/PETM event. According to new magnetic susceptibility data and detailed cycle counting, the entire duration of the CIE/PETM in Zumaia is estimated in ∼168 ± 16 ka. Moreover, the investigation of palynofacies and low-field magnetic susceptibility reveal significant detrital influx during the interval. Several magnetic susceptibility phases and trends are recognised and are interpreted in terms of sea-level fluctuations before, during and after the PETM. Coupled with results from other sections, our data reveal the presence of an unconformity followed by an eustatic sea-level rise (TST) in the latest Palaeocene.
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closing the mid Palaeocene gap toward a complete astronomically tuned Palaeocene epoch and selandian and thanetian gssps at zumaia basque basin w pyrenees
Earth and Planetary Science Letters, 2007Co-Authors: Jaume Dinaresturell, Juan Ignacio Baceta, Gilen Bernaola, Xabier Orueetxebarria, Victoriano PujalteAbstract:Abstract An integrated magneto-, bio- and cyclostratigraphic framework is presented for the Mid-Palaeocene interval from the (hemi)pelagic sea-cliff section of Zumaia in the Basque basin. The new ∼ 55 m long studied section expands about 3.5 Myr and closes the gap between previously published integrated studies in the section. The occurrence of magnetochron C26n is now documented, and its duration (complemented also by data from the Ibaeta section), and that for chrons C26r and C25r is estimated by counting precession related lithologic couplets assigned to have 21-kyr duration (C25r = ∼ 1449 kyr, C26n = ∼ 231 kyr, C26r = ∼ 2877 kyr). Consequently, the Zumaia section now provides the first complete Palaeocene astronomically derived chronology, rendering this section a master reference section. Due to limitations in the orbital calculations and uncertainties in the radiometric dating method no robust tuning and absolute ages can be given for the moment. However, the FOs (First Occurrences) of key calcareous plankton species and the Mid Palaeocene Biotic Event (MPBE) are placed within the magnetostratigraphic and cyclostratigraphic template along the studied Mid-Palaeocene interval. In addition, the dataset provides the key elements for a proper settling of the Thanetian and Selandian Global Stratotype Section and Point (GSSPs), which is one of the primary objectives of the ICS (International Commission of Stratigraphy). We consider the base of chron C26n and the criteria associated to the lithostratigraphic change between the Danian Limestone Fm and the Itzurun marl Fm at Zumaia, as the respective delimiting points for the Thanetian and Selandian bases as recently agreed by the Paleocene Working Group of the International Subcommission of the Paleogene Stratigraphy of the ICS. Consequently, the duration of the Thanetian, Selandian and Danian component stages can be estimated at Zumaia to be about ∼ 3129 kyr, ∼ 2163 kyr and ∼ 4324 kyr respectively (see text for error considerations). However, the MPBE located 8 precession cycles below the base of C26n in correspondence to a short eccentricity maxima at Zumaia, could also serve as a guiding criteria to approximate or redefine the Thanetian base if this level demonstrated synchronous.
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Closing the Mid-Palaeocene gap: Toward a complete astronomically tuned Palaeocene Epoch and Selandian and Thanetian GSSPs at Zumaia (Basque Basin, W Pyrenees)
Earth and Planetary Science Letters, 2007Co-Authors: Jaume Dinarès-turell, Gilen Bernaola, Juan Ignacio Baceta, Xabier Orue-etxebarria, Victoriano PujalteAbstract:An integrated magneto-, bio- and cyclostratigraphic framework is presented for the Mid-Palaeocene interval from the (hemi) pelagic sea-cliff section of Zumaia in the Basque basin. The new ∼55 m long studied section expands about 3.5 Myr and closes the gap between previously published integrated studies in the section. The occurrence of magnetochron C26n is now documented, and its duration (complemented also by data from the Ibaeta section), and that for chrons C26r and C25r is estimated by counting precession related lithologic couplets assigned to have 21-kyr duration (C25r=∼1449 kyr, C26n=∼231 kyr, C26r=∼2877 kyr). Consequently, the Zumaia section now provides the first complete Palaeocene astronomically derived chronology, rendering this section a master reference section. Due to limitations in the orbital calculations and uncertainties in the radiometric dating method no robust tuning and absolute ages can be given for the moment. However, the FOs (First Occurrences) of key calcareous plankton species and the Mid Palaeocene Biotic Event (MPBE) are placed within the magnetostratigraphic and cyclostratigraphic template along the studied Mid-Palaeocene interval. In addition, the dataset provides the key elements for a proper settling of the Thanetian and Selandian Global Stratotype Section and Point (GSSPs), which is one of the primary objectives of the ICS (International Commission of Stratigraphy). We consider the base of chron C26n and the criteria associated to the lithostratigraphic change between the Danian Limestone Fm and the Itzurun marl Fm at Zumaia, as the respective delimiting points for the Thanetian and Selandian bases as recently agreed by the Paleocene Working Group of the International Subcommission of the Paleogene Stratigraphy of the ICS. Consequently, the duration of the Thanetian, Selandian and Danian component stages can be estimated at Zumaia to be about ∼3129 kyr, ∼2163 kyr and ∼4324 kyr respectively (see text for error considerations). However, the MPBE located 8 precession cycles below the base of C26n in correspondence to a short eccentricity maxima at Zumaia, could also serve as a guiding criteria to approximate or redefine the Thanetian base if this level demonstrated synchronous.Published450–4672.2. Laboratorio di paleomagnetismoJCR Journalreserve
