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Wout Krijgsman - One of the best experts on this subject based on the ideXlab platform.
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From Khersonian drying to Pontian “flooding”: late Miocene stratigraphy and palaeoenvironmental evolution of the Dacian Basin (Eastern Paratethys)
Global and Planetary Change, 2020Co-Authors: Sergei Lazarev, A. De Leeuw, Marius Stoica, Iuliana Vasiliev, Oleg Mandic, C.g.c. Van Baak, Wout KrijgsmanAbstract:Abstract In the late Miocene, a large inland sea known as the Eastern Paratethys stretched out across the present-day Black Sea – Caspian Sea region. The basin was mostly endorheic and its water budget thus strongly dependent on regional climate. The basin was therefore prone to high-amplitude water-level fluctuations and associated turnovers in water chemistry and fauna. Profound palaeoenvironmental changes happened in the Eastern Paratethys during this time period. This article documents the evolution of the Dacian Basin of Romania, the westernmost branch of the Eastern Paratethys, during the time interval between 7.7 and 6.0 Ma. Our integrated study of sedimentary facies, micro- and macro fauna along the Slănicul de Buzău Section was constrained with a timeframe based on magnetostratigraphy. The remarkable 1.3 km-thick sedimentary record, high depositional rate (0.65–1.26 m/kyr) and abundance of fossils along this section provide a unique opportunity to study sedimentary and biotic turnovers in high detail. Our analyses reveal several marked water-level and salinity changes: A predominance of freshwater coastal plain environments, only occasionally flooded, indicates a low water-level in the Khersonian (~7.7–7.63 Ma). The coastal plain deposits are overlain by offshore muds revealing a low mesohaline early Maeotian transgression, which was followed by the installation of littoral/nearshore environments with freshwater molluscs in shallow settings and oligohaline ostracods in slightly deeper settings. Subsequent delta progradation and a prevalence of freshwater fauna in both marginal and more distal environments characterize the late Maeotian. This was followed by a remarkable freshwater transgression that started at 6.3 Ma and led to predominantly offshore deposition. The late Maeotian fossil record suggests brackish water pulses from Lake Pannon (Central Paratethys), followed by mass occurrences of Coelogonia novorossica. At 6.1 Ma, a short influx of meso- to polyhaline microfauna including benthic and planktonic foraminifera defines the “Pontian Salinity Incursion”. Molluscs, including Eupatorina littoralis, that biostratigraphically mark the onset of the Pontian arrived with a negligible delay of ~5 kyr after the microfauna influx. The onset of the Pontian at Slănicul de Buzau at 6.1 Ma (± 5 kyr), is thus synchronous with the onset in other Paratethys basins. Our integrated approach, placing the preserved fossil fauna in its respective sedimentary environment, allows for a detailed insight into the salinity of coeval marginal as well as basinal environments and could be more widely applied in the Paratethys realm and other semi-isolated basins with a deviant salinity.
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Integrated bio-magnetostratigraphy of the Badenian reference section Ugljevik in southern Pannonian Basin - implications for the Paratethys history (middle Miocene, Central Europe)
Global and Planetary Change, 2019Co-Authors: Oleg Mandic, Stjepan Ćorić, Patrick Grunert, Karin Sant, Mădălina Elena Kallanxhi, Dörte Theobalt, Arjan De Leeuw, Wout KrijgsmanAbstract:Abstract The Central Paratethys was a large-scale Oligo-Miocene epicontinental sea located in Central and Eastern Europe. It was separated from the Mediterranean by the Alpine orogenic belt. The Paratethys progressively flooded the Pannonian back-arc basin that formed during the early to middle Miocene. Along the southern margin of the basin, the maximum extension of the Paratethys onto the flanks of the Dinarides Mountains occurred during the middle Miocene (Badenian). We have studied the most complete middle Miocene (Badenian-Sarmatian) Paratethys section located at this southern margin. It comprises a >1.5 Myr long, continuous marine depositional sequence, which is highly relevant for our understanding of the interplay between global climatic and regional geodynamic perturbations in this semi-isolated epicontinental basin. The investigated record is particularly important to assess the impact of the Middle Miocene Climate Transition, the Langhian-Serravallian glacial Mi-3b event, the syn-rift climax of the Pannonian Basin and the Badenian Salinity Crisis. Moreover, we present the first high resolution age model for the regional Badenian stage based on integrated biomagnetostratigraphy. According to our age model, the marine flooding reached the area at ~14.15 Ma, during the regional Badenian stage. Open marine conditions persisted until ~12.6 Ma when the extinction of the fully marine fauna marks the beginning of the regional Sarmatian stage. Sea-level fluctuations are reflected in the section by four transgressive regressive cycles coinciding roughly with 400-kyr-eccentricity periods. The largest sea-level fall occurred after the first cycle and corresponds to the end of the Middle Miocene Climate Transition marked by glacial event Mi-3b. Elsewhere in the Pannonian Basin, this marked drop in base-level triggered deposition of evaporites during the Badenian Salinity Crisis. At Ugljevik however, there are no evaporites and the short-term Mi-3b regression was followed by a transgression and re-establishment of deeper marine conditions at 13.76 Ma, i.e. during the earliest Serravallian. Diversified planktonic and benthic assemblages suggest fully marine conditions with a persistent connection to the Mediterranean at this time. Such conditions prevailed until the mid Serravallian (latest Badenian) when sediment input increased and coastal environments prograded seawards. The Badenian/Sarmatian boundary roughly coincided with a 400-kyr-eccentricity as well as with a 1.2-Myr obliquity minimum.
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The Eocene-Oligocene transition in the North Alpine Foreland Basin and subsequent closure of a Paratethys gateway
Global and Planetary Change, 2018Co-Authors: A. Van Der Boon, Reinhard F. Sachsenhofer, Arjen Grothe, Cor G. Langereis, A. Beniest, Agnieszka Ciurej, E. Gaździcka, Wout KrijgsmanAbstract:During the Eocene-Oligocene transition (EOT), a major palaeoenvironmental change took place in the Paratethys Sea of central Eurasia. Restricted connectivity and increased stratification resulted in wide-spread deposition of organic-rich sediments which nowadays make up important hydrocarbon source rocks. The North Alpine Foreland Basin (NAFB) was a major gateway of the Paratethys Sea to the open ocean during the Eocene, but the age of closure of this gateway is still uncertain. The Ammer section in southern Germany documents the shallowing of this connection and subsequent disappearance of marine environments in the NAFB, as reflected in its sedimentary succession of turbidites to marls (Deutenhausen to Tonmergel beds), via coastal sediments (Baustein beds) to continental conglomerates (Weisach beds). Here, we apply organic geochemistry and date the lithological transitions in the Ammer section using integrated stratigraphy, including magnetostratigraphy and biostratigraphy. Nannoplankton and dinocyst results can be reconciled when dinoflagellate species Wetzeliella symmetrica is of late Eocene age. Our magnetostratigraphy then records C13r-C13n-C12r and allows calculation of sediment accumulation rates and estimation of ages of lithological transitions. We show that the shallowing from turbiditic slope deposits (Deutenhausen beds) to shelf sediments (Tonmergel beds) coincides with the Eocene-Oligocene boundary at 33.9 Ma. The transition to continental sediments is dated at ca. 33.15 Ma, significantly older than suggested by previous studies. We conclude that the transition from marine to continental sediments drastically reduced the marine connection through the western part of the NAFB and influenced the oxygen conditions of the Paratethys Sea.
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Early diagenetic greigite as an indicator of paleosalinity changes in the middle Miocene Paratethys Sea of central Europe
Geochemistry Geophysics Geosystems, 2017Co-Authors: Suzhen Liu, Wout Krijgsman, Mark J. Dekkers, D. V. PalcuAbstract:The Miocene epicontinental Paratethys Sea of central Eurasia has experienced multiple restriction and reconnection events to the open ocean. Magnetostratigraphy is an important dating tool to better understand the temporal and spatial paleoenvironmental variations associated with these changes. Magnetostratigraphy in the Paratethys domain, however, is complicated by the presence of greigite (Fe3S4). Here we report rock magnetic and X-ray fluorescence data of the Tisa section (Romania) which was previously magnetostratigraphically dated at the middle Miocene (base at 12.8 Ma and top at 12.2 Ma). This section comprises the Badenian Sarmatian Extinction Event (BSEE), which is marked by a major salinity change from marine to brackish environments, related to the opening of the connection between the Central and the Eastern Paratethys basins. In the marine Badenian sediments below the BSEE, the pyritization process is shown to be complete because of abundant sulfate supply. In the brackish Sarmatian deposits, four intervals with early diagenetic greigite are observed, and linked to insufficient sulfate in the water column. These four greigite intervals appear to correspond to maxima in the ∼100 kyr eccentricity cycle. We propose that increased fresh water from the Eastern Paratethys basin during eccentricity maxima restricted the sulfate availability in the Tisa area, leading to a reduced HS− production and enhanced greigite preservation. The early diagenetic formation of greigite enables a quasi syn-depositional recording of the paleomagnetic field, which allows reliable paleomagnetic dating in this section. Our results further suggest greigite as a potential indicator for salinity changes during marine/brackish transitions.
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changing seas in the early middle miocene of central europe a mediterranean approach to paratethyan stratigraphy
Terra Nova, 2017Co-Authors: Karin Sant, D. V. Palcu, Oleg Mandic, Wout KrijgsmanAbstract:The Miocene palaeogeographic evolution of the Paratethys Sea is still poorly constrained. Here, we use modern Mediterranean biochronology to provide an up-to-date overview of changing seas in Central Europe. Instead of a Paratethys sea that waxed and waned with fluctuating global sea level, we show that the evolution of different seas was mainly controlled by tectonic phases. The Early Miocene “Ottnangian Sea” (~18 Ma) was connected to the Mediterranean via the Rhone valley, while the “Karpatian Sea” (~16.5 Ma) was initiated by a tectonically induced marine transgression through the Trans-Tethyan gateway. In most Central European basins the establishment of the “Badenian Sea” (<15.2 Ma), triggered by subduction-related processes in the Pannonian and Carpathian domain, is significantly younger (by ~1 Myr) than usually estimated. The updated palaeogeographic reconstructions provide a better understanding of the concepts of basin dynamics, land–sea distribution and palaeoenvironmental change in the Miocene of Central Europe. This article is protected by copyright. All rights reserved.
Marius Stoica - One of the best experts on this subject based on the ideXlab platform.
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From Khersonian drying to Pontian “flooding”: late Miocene stratigraphy and palaeoenvironmental evolution of the Dacian Basin (Eastern Paratethys)
Global and Planetary Change, 2020Co-Authors: Sergei Lazarev, A. De Leeuw, Marius Stoica, Iuliana Vasiliev, Oleg Mandic, C.g.c. Van Baak, Wout KrijgsmanAbstract:Abstract In the late Miocene, a large inland sea known as the Eastern Paratethys stretched out across the present-day Black Sea – Caspian Sea region. The basin was mostly endorheic and its water budget thus strongly dependent on regional climate. The basin was therefore prone to high-amplitude water-level fluctuations and associated turnovers in water chemistry and fauna. Profound palaeoenvironmental changes happened in the Eastern Paratethys during this time period. This article documents the evolution of the Dacian Basin of Romania, the westernmost branch of the Eastern Paratethys, during the time interval between 7.7 and 6.0 Ma. Our integrated study of sedimentary facies, micro- and macro fauna along the Slănicul de Buzău Section was constrained with a timeframe based on magnetostratigraphy. The remarkable 1.3 km-thick sedimentary record, high depositional rate (0.65–1.26 m/kyr) and abundance of fossils along this section provide a unique opportunity to study sedimentary and biotic turnovers in high detail. Our analyses reveal several marked water-level and salinity changes: A predominance of freshwater coastal plain environments, only occasionally flooded, indicates a low water-level in the Khersonian (~7.7–7.63 Ma). The coastal plain deposits are overlain by offshore muds revealing a low mesohaline early Maeotian transgression, which was followed by the installation of littoral/nearshore environments with freshwater molluscs in shallow settings and oligohaline ostracods in slightly deeper settings. Subsequent delta progradation and a prevalence of freshwater fauna in both marginal and more distal environments characterize the late Maeotian. This was followed by a remarkable freshwater transgression that started at 6.3 Ma and led to predominantly offshore deposition. The late Maeotian fossil record suggests brackish water pulses from Lake Pannon (Central Paratethys), followed by mass occurrences of Coelogonia novorossica. At 6.1 Ma, a short influx of meso- to polyhaline microfauna including benthic and planktonic foraminifera defines the “Pontian Salinity Incursion”. Molluscs, including Eupatorina littoralis, that biostratigraphically mark the onset of the Pontian arrived with a negligible delay of ~5 kyr after the microfauna influx. The onset of the Pontian at Slănicul de Buzau at 6.1 Ma (± 5 kyr), is thus synchronous with the onset in other Paratethys basins. Our integrated approach, placing the preserved fossil fauna in its respective sedimentary environment, allows for a detailed insight into the salinity of coeval marginal as well as basinal environments and could be more widely applied in the Paratethys realm and other semi-isolated basins with a deviant salinity.
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Mediterranean-Paratethys connectivity during the Messinian salinity crisis: The Pontian of Azerbaijan
Global and Planetary Change, 2016Co-Authors: Christiaan G.c. Van Baak, Marius Stoica, Arjen Grothe, E. Aliyeva, Wout KrijgsmanAbstract:Abstract Prior to the onset of the Messinian Salinity Crisis, a connection was established between the Mediterranean Sea and the Paratethys region to the north. Rivers currently draining into the Caspian Sea thereby became important for the Mediterranean hydrological budget. The role of this connection and the influence of the Paratethys on the hydrological budget of the Mediterranean Sea during the Messinian Salinity Crisis is however poorly understood because of a lack of records in the Paratethys with a high-resolution (cyclostratigraphic) age model. Here, we present a high-resolution integrated stratigraphic study of a key section in the Caspian Sea region (Azerbaijan), to assess the connectivity of the Caspian Sea during the salinity crisis. The studied section spans the time interval between ~ 6.16 Ma and
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Tectono-climatic implications of Eocene Paratethys regression in the Tajik basin of central Asia
Earth and Planetary Science Letters, 2015Co-Authors: Barbara Carrapa, Marius Stoica, Peter G. Decelles, Xin Wang, Mark T. Clementz, Nicoletta Mancin, Brian P. Kraatz, Jin Meng, Sherzod Abdulov, Fahu ChenAbstract:Abstract Plate tectonics and eustatic sea-level changes have fundamental effects on paleoenvironmental conditions and bio-ecological changes. The Paratethys Sea was a large marine seaway that connected the Mediterranean Neotethys Ocean with Central Asia during early Cenozoic time. Withdrawal of the Paratethys from central Asia impacted the distribution and composition of terrestrial faunas in the region and has been largely associated with changes in global sea level and climate such as cooling associated with the Eocene/Oligocene transition (EOT). Whereas the regression has been dated in the Tarim basin (China), the pattern and timing of regression in the Tajik basin, 400 km to the west, remain unresolved, precluding a test of current paleogeographic models. Here we date the Paratethys regression in Tajikistan at ca. 39 million years ago (Ma), which is several million years older than the EOT (at ca. 34 Ma) marking the greenhouse to icehouse climate transition of the Cenozoic. Our data also show a restricted, evaporitic marine environment since the middle–late Eocene and establishment of desert like environments after ca. 39 Ma. The overall stratigraphic record from the Tajik basin and southern Tien Shan points to deposition in a foreland basin setting by ca. 40 Ma in response to active tectonic growth of the Pamir–Tibet Mountains at the same time. Combined with the northwestward younging trend of the regression in the region, the Tajik basin record is consistent with northward growth of the Pamir and suggests significant tectonic control on Paratethys regression and paleoenvironmental changes in Central Asia.
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Miocene connectivity between the Central and Eastern Paratethys: Constraints from the western Dacian Basin
Palaeogeography Palaeoclimatology Palaeoecology, 2014Co-Authors: Marten Ter Borgh, Marius Stoica, Marinus E. Donselaar, Liviu Matenco, Wout KrijgsmanAbstract:Abstract The Dacian Basin formed an important link between the central and eastern parts of the Paratethys, a chain of late Tertiary inland seas and lakes. This study presents constraints on Miocene sea and lake level fluctuations in the Dacian Basin and on the connectivity between it and other Paratethys basins, based on the interpretation of seismic lines, a micropalaeontological study and lithofacies analysis of a large number of outcrops. It is shown that relative sea level fluctuations in the western part of the Dacian Basin during the Middle Miocene were primarily driven by tectonic activity in the nearby Carpathian Mountains. From the Maeotian (Late Miocene) onwards, however, tectonic activity was minor and relative sea level fluctuations were primarily driven by changes in basin connectivity and climate. The connection between the Central and Eastern Paratethys was broken at the end of the Middle Miocene, leading to the development of an endemic fauna in the former, but new data presented here suggest that isolation was not sustained completely as Central Paratethys species appeared in the Dacian Basin during the Maeotian (Late Miocene). Besides the isolation two falls in water level occurred in the basin during the latest Miocene: Of these, the intra-Pontian sea-level drop is the best known. We show, however, that this drop was preceded by a larger sea or lake-level drop in the late Sarmatian/Maeotian. This latter event may have affected much larger parts of the Paratethys, and we recommend more study of the bordering basins. The hypothesis that the connection between the Dacian and Central Paratethys basins was located in the region where the Danube River presently crosses the Carpathians was tested, but no supporting evidence was found.
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Dating the isolation of the Central Paratethys: new constraints from magnetostratigraphy (Beocin section, northern Serbia)
2010Co-Authors: Marten Ter Borgh, Wout Krijgsman, Marius Stoica, Iuliana Vasiliev, Liviu Matenco, Slobodan Knežević, Sierd CloetinghAbstract:The Paratethys was a large network of inland seas that once extended over Europe from the Alps to the Caspian Sea. Since the Miocene, the Paratethys Sea retreated eastward to the present-day Black Sea, whereby various subbasins became progressively isolated from the global ocean. The isolation of the Central Paratethys was marked by a change from restricted marine to brackish paleoenvironmental conditions. These changes were associated with a marked sea-level drop. Whether this drop was the result of tectonics in the Carpathians chain and/or regional eustatic variations is still debated. In order to correlate the paleo-environmental changes and to solve the puzzle of the onset of the evolution of this endemic lake, knowing the absolute age of this transition is critical. It is known that the Central Paratethys region was isolated from other parts of the Paratethys at the transition between the Sarmatian (Middle to Late Miocene) and Pannonian (Late Miocene) stages. The absolute age of this transition is still unknown, however. Whether the transition occurred synchronously or diachronously in the different subbasins, is also still unknown. To establish this absolute age, we present here magnetostratigraphic results from the Beoˇ cin quarry (northern Serbia) on the Fruoka Gora inselberg in the Pannonian plain, where a relatively long section of Sarmatian and Pannonian deposits is present. In total, almost 800 levels distributed over 4 sections in roughly 130 m of stratigraphy were sampled. Biostratigraphic analyses focussed on foraminifera and ostracod data. We will compare our integrated stratigraphic results with recent data from the Styrian basin (Austria) and the Transylvanian basin (Romania). This will help us establish whether the transition occurred synchronously or diachronously across the sub-basins, and to unravel the contributions to the isolation event of global eustatic sea level changes from regional tectonic events.
Iuliana Vasiliev - One of the best experts on this subject based on the ideXlab platform.
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From Khersonian drying to Pontian “flooding”: late Miocene stratigraphy and palaeoenvironmental evolution of the Dacian Basin (Eastern Paratethys)
Global and Planetary Change, 2020Co-Authors: Sergei Lazarev, A. De Leeuw, Marius Stoica, Iuliana Vasiliev, Oleg Mandic, C.g.c. Van Baak, Wout KrijgsmanAbstract:Abstract In the late Miocene, a large inland sea known as the Eastern Paratethys stretched out across the present-day Black Sea – Caspian Sea region. The basin was mostly endorheic and its water budget thus strongly dependent on regional climate. The basin was therefore prone to high-amplitude water-level fluctuations and associated turnovers in water chemistry and fauna. Profound palaeoenvironmental changes happened in the Eastern Paratethys during this time period. This article documents the evolution of the Dacian Basin of Romania, the westernmost branch of the Eastern Paratethys, during the time interval between 7.7 and 6.0 Ma. Our integrated study of sedimentary facies, micro- and macro fauna along the Slănicul de Buzău Section was constrained with a timeframe based on magnetostratigraphy. The remarkable 1.3 km-thick sedimentary record, high depositional rate (0.65–1.26 m/kyr) and abundance of fossils along this section provide a unique opportunity to study sedimentary and biotic turnovers in high detail. Our analyses reveal several marked water-level and salinity changes: A predominance of freshwater coastal plain environments, only occasionally flooded, indicates a low water-level in the Khersonian (~7.7–7.63 Ma). The coastal plain deposits are overlain by offshore muds revealing a low mesohaline early Maeotian transgression, which was followed by the installation of littoral/nearshore environments with freshwater molluscs in shallow settings and oligohaline ostracods in slightly deeper settings. Subsequent delta progradation and a prevalence of freshwater fauna in both marginal and more distal environments characterize the late Maeotian. This was followed by a remarkable freshwater transgression that started at 6.3 Ma and led to predominantly offshore deposition. The late Maeotian fossil record suggests brackish water pulses from Lake Pannon (Central Paratethys), followed by mass occurrences of Coelogonia novorossica. At 6.1 Ma, a short influx of meso- to polyhaline microfauna including benthic and planktonic foraminifera defines the “Pontian Salinity Incursion”. Molluscs, including Eupatorina littoralis, that biostratigraphically mark the onset of the Pontian arrived with a negligible delay of ~5 kyr after the microfauna influx. The onset of the Pontian at Slănicul de Buzau at 6.1 Ma (± 5 kyr), is thus synchronous with the onset in other Paratethys basins. Our integrated approach, placing the preserved fossil fauna in its respective sedimentary environment, allows for a detailed insight into the salinity of coeval marginal as well as basinal environments and could be more widely applied in the Paratethys realm and other semi-isolated basins with a deviant salinity.
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Dating the isolation of the Central Paratethys: new constraints from magnetostratigraphy (Beocin section, northern Serbia)
2010Co-Authors: Marten Ter Borgh, Wout Krijgsman, Marius Stoica, Iuliana Vasiliev, Liviu Matenco, Slobodan Knežević, Sierd CloetinghAbstract:The Paratethys was a large network of inland seas that once extended over Europe from the Alps to the Caspian Sea. Since the Miocene, the Paratethys Sea retreated eastward to the present-day Black Sea, whereby various subbasins became progressively isolated from the global ocean. The isolation of the Central Paratethys was marked by a change from restricted marine to brackish paleoenvironmental conditions. These changes were associated with a marked sea-level drop. Whether this drop was the result of tectonics in the Carpathians chain and/or regional eustatic variations is still debated. In order to correlate the paleo-environmental changes and to solve the puzzle of the onset of the evolution of this endemic lake, knowing the absolute age of this transition is critical. It is known that the Central Paratethys region was isolated from other parts of the Paratethys at the transition between the Sarmatian (Middle to Late Miocene) and Pannonian (Late Miocene) stages. The absolute age of this transition is still unknown, however. Whether the transition occurred synchronously or diachronously in the different subbasins, is also still unknown. To establish this absolute age, we present here magnetostratigraphic results from the Beoˇ cin quarry (northern Serbia) on the Fruoka Gora inselberg in the Pannonian plain, where a relatively long section of Sarmatian and Pannonian deposits is present. In total, almost 800 levels distributed over 4 sections in roughly 130 m of stratigraphy were sampled. Biostratigraphic analyses focussed on foraminifera and ostracod data. We will compare our integrated stratigraphic results with recent data from the Styrian basin (Austria) and the Transylvanian basin (Romania). This will help us establish whether the transition occurred synchronously or diachronously across the sub-basins, and to unravel the contributions to the isolation event of global eustatic sea level changes from regional tectonic events.
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Strontium isotope ratios of the Eastern Paratethys during the Mio-Pliocene transition; Implications for interbasinal connectivity
Earth and Planetary Science Letters, 2010Co-Authors: Iuliana Vasiliev, Wout Krijgsman, Gert-jan Reichart, Gareth R. Davies, Marius StoicaAbstract:Paratethys represents the large basin that extended from central Europe to inner Asia, comprising the North Alpine foreland, Pannonian and Dacian basins, the Black Sea and Caspian Sea. Connectivity between these subbasins and the connectivity of Paratethys with the open ocean varied drastically because of pervasive tectono-climatic processes affecting the region. Here, we investigate the biogenically produced carbonates of the Dacian basin for strontium analyses to monitor changes in connectivity, water geochemistry and palaeoenvironment during the Mio-Pliocene transition. Diagenetic evaluation showed that not all contamination could be removed, but that the strontium content of our samples was not affected by post-depositional processes. 87Sr/86Sr ratios of ostracods and molluscs are in good agreement and show relatively constant values of 0.70865–0.70885. These are much lower than coeval Mio-Pliocene ocean water (0.7089–0.7090), which indicates that no long-standing connection existed to the Mediterranean. The newly obtained strontium ratios for Paratethys are best explained by a mixture of Danube, Dnieper and Don river waters, implying connectivity between Dacian basin and Black Sea during the latest Miocene–earliest Pliocene. We observed no evidence for connectivity to the Caspian Sea during this period. The 87Sr/86Sr ratios of the Dacian basin are similar to the ones measured in the Mediterranean “Upper Evaporites/Lago Mare” facies. The major fresh water deluge at the end of the Messinian salinity crisis could thus have been caused by drowning of Eastern Paratethys waters into the Mediterranean.
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Rise and fall of the Paratethys Sea during the Messinian Salinity Crisis
Earth and Planetary Science Letters, 2010Co-Authors: Wout Krijgsman, Marius Stoica, Iuliana Vasiliev, V.v. PopovAbstract:Abstract Extremely thick evaporite units were deposited during the so-called Messinian Salinity Crisis (MSC: 5.96–5.33 Ma) in a deep Mediterranean basin that was progressively disconnected from the Atlantic Ocean. A crucial, but still poorly understood component in Messinian evaporite models is the connectivity between Mediterranean and Paratethys, i.e. the former Black Sea domain. Inadequate stratigraphic correlations and insufficient age control for Paratethys sediments have so far hampered a thorough understanding of hydrological fluxes and paleoenvironmental changes. Here, we present a new chronology for the Eastern Paratethys by integrating biostratigraphic and paleomagnetic data from Mio–Pliocene sedimentary successions of Romania and Russia. We show that a major flooding event from the Mediterranean surged the Paratethys basins at the Maeotian–Pontian boundary, 6.04 million years ago. This indicates that sea level in both Mediterranean and Paratethys was high at the beginning of the MSC. We argue in favor of changes in Paratethys–Mediterranean connectivity to initiate the MSC in combination with elusive tectonic processes in the Gibraltar arc. A subsequent fall of Paratethyan water level closely coincides to the Mediterranean isolation-event, corresponding in age to the glacial cycles TG12–14 (5.60–5.50 Myr). In the latest Messinian, a major climate change towards more humid conditions produced a positive hydrological balance and likely a transgression in the Paratethys, although our stratigraphic resolution cannot exclude a possible relation to the Pliocene flooding of the Mediterranean here.
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mio pliocene magnetostratigraphy in the southern carpathian foredeep and mediterranean Paratethys correlations
Terra Nova, 2005Co-Authors: Iuliana Vasiliev, Wout Krijgsman, Marius Stoica, Cor G. LangereisAbstract:A full understanding of the Mio-Pliocene palaeogeographical and palaeoenvironmental changes in the circum-Mediterranean region during the Messinian Salinity Crisis (MSC) is at present hampered by the lack of reliable chronostratigraphic correlations between the Mediterranean and Paratethys regions. Here, we present magnetostratigraphic ages for the Upper Miocene to Pliocene deposits of the southern Carpathian foredeep in Romania. These ages are in good agreement with those recently obtained from the eastern Carpathian foredeep and define a new chronology for the eastern Paratethys. The Meotian/Pontian boundary is not biostratigraphically
Cor G. Langereis - One of the best experts on this subject based on the ideXlab platform.
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The Eocene-Oligocene transition in the North Alpine Foreland Basin and subsequent closure of a Paratethys gateway
Global and Planetary Change, 2018Co-Authors: A. Van Der Boon, Reinhard F. Sachsenhofer, Arjen Grothe, Cor G. Langereis, A. Beniest, Agnieszka Ciurej, E. Gaździcka, Wout KrijgsmanAbstract:During the Eocene-Oligocene transition (EOT), a major palaeoenvironmental change took place in the Paratethys Sea of central Eurasia. Restricted connectivity and increased stratification resulted in wide-spread deposition of organic-rich sediments which nowadays make up important hydrocarbon source rocks. The North Alpine Foreland Basin (NAFB) was a major gateway of the Paratethys Sea to the open ocean during the Eocene, but the age of closure of this gateway is still uncertain. The Ammer section in southern Germany documents the shallowing of this connection and subsequent disappearance of marine environments in the NAFB, as reflected in its sedimentary succession of turbidites to marls (Deutenhausen to Tonmergel beds), via coastal sediments (Baustein beds) to continental conglomerates (Weisach beds). Here, we apply organic geochemistry and date the lithological transitions in the Ammer section using integrated stratigraphy, including magnetostratigraphy and biostratigraphy. Nannoplankton and dinocyst results can be reconciled when dinoflagellate species Wetzeliella symmetrica is of late Eocene age. Our magnetostratigraphy then records C13r-C13n-C12r and allows calculation of sediment accumulation rates and estimation of ages of lithological transitions. We show that the shallowing from turbiditic slope deposits (Deutenhausen beds) to shelf sediments (Tonmergel beds) coincides with the Eocene-Oligocene boundary at 33.9 Ma. The transition to continental sediments is dated at ca. 33.15 Ma, significantly older than suggested by previous studies. We conclude that the transition from marine to continental sediments drastically reduced the marine connection through the western part of the NAFB and influenced the oxygen conditions of the Paratethys Sea.
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mio pliocene magnetostratigraphy in the southern carpathian foredeep and mediterranean Paratethys correlations
Terra Nova, 2005Co-Authors: Iuliana Vasiliev, Wout Krijgsman, Marius Stoica, Cor G. LangereisAbstract:A full understanding of the Mio-Pliocene palaeogeographical and palaeoenvironmental changes in the circum-Mediterranean region during the Messinian Salinity Crisis (MSC) is at present hampered by the lack of reliable chronostratigraphic correlations between the Mediterranean and Paratethys regions. Here, we present magnetostratigraphic ages for the Upper Miocene to Pliocene deposits of the southern Carpathian foredeep in Romania. These ages are in good agreement with those recently obtained from the eastern Carpathian foredeep and define a new chronology for the eastern Paratethys. The Meotian/Pontian boundary is not biostratigraphically
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Mio‐Pliocene magnetostratigraphy in the southern Carpathian foredeep and Mediterranean–Paratethys correlations
Terra Nova, 2005Co-Authors: Iuliana Vasiliev, Wout Krijgsman, Marius Stoica, Cor G. LangereisAbstract:A full understanding of the Mio-Pliocene palaeogeographical and palaeoenvironmental changes in the circum-Mediterranean region during the Messinian Salinity Crisis (MSC) is at present hampered by the lack of reliable chronostratigraphic correlations between the Mediterranean and Paratethys regions. Here, we present magnetostratigraphic ages for the Upper Miocene to Pliocene deposits of the southern Carpathian foredeep in Romania. These ages are in good agreement with those recently obtained from the eastern Carpathian foredeep and define a new chronology for the eastern Paratethys. The Meotian/Pontian boundary is not biostratigraphically
Dabang Jiang - One of the best experts on this subject based on the ideXlab platform.
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what triggers the transition of palaeoenvironmental patterns in china the tibetan plateau uplift or the Paratethys sea retreat
Palaeogeography Palaeoclimatology Palaeoecology, 2007Co-Authors: Zhang Zhongshi, Huijun Wang, Zhengtang Guo, Dabang JiangAbstract:Abstract Geological research has illustrated the transition of palaeoenvironmental patterns by the earliest Miocene from a planetary-wind-dominant type to a monsoon-dominant type, indicating that the East Asian monsoon became markedly intensified and played a leading role in the East Asian climate. From a modeling point of view, the pioneering research using the reduced number of scenarios had demonstrated that both the Tibetan Plateau uplift and the Paratethys Sea retreat were important for understanding the Asian monsoon evolution. However, the sensitivity of the Paratethys retreat to the East Asian climate still needs further studies based on the more detailed scenarios. Thirty numerical experiments under the six Paratethys Sea and the five Tibetan Plateau conditions illustrate the shifts from zonal climate to the monsoon climate in East Asia. The results confirm again that both the Paratethys retreat and the Tibetan plateau uplift play important roles in the formation of the monsoon-dominant environmental pattern, and show that the Paratethys retreat can strengthen the East Asian monsoon and greatly increase humidity and aridity respectively in the monsoon areas and Northwest China, which is similar to the impact of the Tibetan Plateau uplift on the East Asian climate. Furthermore, the fact that the Paratethys Sea retreats to the Turan Plate is found to be the key criterion for the palaeoenvironmental patterns' transition in China. The shrinkage of Paratethys Sea leads to the reconstructions of the pressure system and the atmospheric circulations, which result in the variations of precipitation and the transition of palaeoenvironmental patterns.
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What triggers the transition of palaeoenvironmental patterns in China；the Tibetan Plateau uplift or the Paratethys Sea retreat?
Palaeogeography Palaeoclimatology Palaeoecology, 2006Co-Authors: Zhang Zhongshi, Huijun Wang, Zhengtang Guo, Dabang JiangAbstract:Abstract Geological research has illustrated the transition of palaeoenvironmental patterns by the earliest Miocene from a planetary-wind-dominant type to a monsoon-dominant type, indicating that the East Asian monsoon became markedly intensified and played a leading role in the East Asian climate. From a modeling point of view, the pioneering research using the reduced number of scenarios had demonstrated that both the Tibetan Plateau uplift and the Paratethys Sea retreat were important for understanding the Asian monsoon evolution. However, the sensitivity of the Paratethys retreat to the East Asian climate still needs further studies based on the more detailed scenarios. Thirty numerical experiments under the six Paratethys Sea and the five Tibetan Plateau conditions illustrate the shifts from zonal climate to the monsoon climate in East Asia. The results confirm again that both the Paratethys retreat and the Tibetan plateau uplift play important roles in the formation of the monsoon-dominant environmental pattern, and show that the Paratethys retreat can strengthen the East Asian monsoon and greatly increase humidity and aridity respectively in the monsoon areas and Northwest China, which is similar to the impact of the Tibetan Plateau uplift on the East Asian climate. Furthermore, the fact that the Paratethys Sea retreats to the Turan Plate is found to be the key criterion for the palaeoenvironmental patterns' transition in China. The shrinkage of Paratethys Sea leads to the reconstructions of the pressure system and the atmospheric circulations, which result in the variations of precipitation and the transition of palaeoenvironmental patterns.
