Changing Sediment Supply During Glacial-Interglacial Intervals in the North Atlantic Revealed by Particle Size Characterization and Environmental Magnetism
The Dire Straits of Paratethys : Dating, matching and modeling connectivity between the Miocene seas of Eurasia
Prehistoric Eurasia contained the largest mega-lake on Earth, formed after the isolation of a fra... more Prehistoric Eurasia contained the largest mega-lake on Earth, formed after the isolation of a fragmented region of dying seas known as Paratethys. In this realm, tectonics, sea-level fluctuations, and climate change led to ecological crises: brine seas, extinctions, great drying events and mega-floods. How these cataclysmic events were connected remained a mystery. This study shows that central to these catastrophes are the sea-straits. We document how small changes in climate or in sea-level can change the behavior of the straits and then lead to environmental change and even extinction events. Also, we postulate that a large number of previously unexplained anomalies, stretching for thousands of km are marks of a large mega-flood that occurred when the Eurasian mega-lake spilled large amounts of water into the Mediterranean Sea and we clarify the mechanism that triggered a second mega-flood that would temporarily transform the Mediterranean sea into a brackish lake (Lago Mare). We conclude that sea-straits are one of the most sensitive parts of our planet’s pluming, likely to disrupt the balance between seas and ocean and trigger environmental crises in the context of sea-level and climate change
Litho-and biostratigraphic data are provided of 5 stratigraphic sections in Romania covering the ... more Litho-and biostratigraphic data are provided of 5 stratigraphic sections in Romania covering the "Badenian" marine flooding that occurred in the Central Paratethys during the middle Miocene (Langhian). The dataset includes stratigraphic logs and descriptions of the profiles, and biostratigraphic analyses on calcareous nannofossils and foraminifera. In addition, characteristic stratigraphic features and representative fossils, including tiny Streptochilus foraminifera in the Campinit¸a section in the SE Carpathian Foredeep, are presented in photographs. The data show that the flooding is characterized by the sudden abundance of Langhian calcareous nannofossils and foraminifera with a strong Mediterranean affinity.
Palaeogeography, Palaeoclimatology, Palaeoecology, Dec 1, 2019
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
International Journal of Earth Sciences, Aug 10, 2019
The mid-Langhian ("Badenian") flooding fully reconnected the semi-isolated Central Paratethys rea... more The mid-Langhian ("Badenian") flooding fully reconnected the semi-isolated Central Paratethys realm with the Mediterranean and, thereby, drastically changed the middle Miocene paleogeography of Central Europe. Due to the scattered stratigraphic record and scarcity of independent age constraints in some areas, the precise age and underlying mechanism are still debated. We present integrated chronostratigraphic data from five sections in the eastern part of the system to reconstruct the flooding event distal from the strait to the Mediterranean. By applying modern Mediterranean biochronology (planktonic foraminifera and calcareous nannofossils), supplemented by an 40 Ar/ 39 Ar age on a tuff, we demonstrate that the widespread open marine settings in the NW Transylvanian Basin were definitely installed after 14.9 Ma (MMi4d biozone), and in most areas before 14.4 Ma. In the marginal study area in the SE Carpathian Foredeep, fully marine conditions likely set in slightly later (14.6-14.4 Ma). There, short-lived marine incursions into the brackish environment occurred since the latest Burdigalian ("pre-flooding phase"). The new ages overlap with the flooding in the majority of the Central Paratethys (~ 14.9-14.4 Ma), and with marine overflow into the Black Sea (14.85 Ma). We suggest that the transgression was driven by subsidence of the Pannonian Basin, by creating accommodation space and diminishing barriers between sub-basins, but was likely enhanced by a global sea-level rise. Finally, we speculate that the scarcity of all calcareous material in the SE Carpathian Foredeep before the mid-Langhian flooding might be related to pulses of nutrient-rich brackish and low pH water from the neighboring Black Sea Basin.
The demise of Paratethys in the time of the Messinian Salinity Crisis: impact on Eurasian paleogeography and Mediterranean environments
During the Messinian Salinity Crisis (MSC), as the Mediterranean realm experienced partial desicc... more During the Messinian Salinity Crisis (MSC), as the Mediterranean realm experienced partial desiccation, water levels in Paratethys, a vast waterbody in the middle of Eurasia, remained largely unaffected except in its easternmost domain, the Caspian basin, which experienced a severe partial desiccation. Still, its relation and role in the dynamics of the MSC are controversial.Here we reconstruct the paleogeographic evolution of the Paratethys region during the MSC. We show that the Paratethys realm irreversibly fragmented into smaller basins (Dacian, Black Sea, Caspian) triggering a reorganization of the Paratethys watershed during the MSC. The Paleo-Don River, the main river flowing in Paratethys, was captured by the Black Sea basin enhancing the excess of water was spilled in the Mediterranean and affecting the hydrology of the Mediterranean during the Lago Mare phase of the MSC. The Caspian basin, isolated and deprived of major river inflows, became partially desiccated, experien...
American Journal of Physical Anthropology, Mar 1, 2020
The 2020 AAPA abstract issue includes 1222 peer-reviewed scienti c papers, which will be presente... more The 2020 AAPA abstract issue includes 1222 peer-reviewed scienti c papers, which will be presented in either podium or poster sessions at the annual meeting in Los Angeles, California. Once again, our program is truly international, with scientists from all over the world including Africa, Asia, Australia, Europe, Latin America, and the Middle East. We are pleased to be joined in Los Angeles by our partner organizations, the Paleopathology Association (PPA), the Human Biology Association (HBA), the American Association for Anthropological Genetics (AAAG), and the Dental Anthropology Association (DAA) and the Paleoanthropology Society (PAS). Abstracts are presented alphabetically by the last name of the rst author. The abstracts illustrate the remarkable capabilities of our discipline, covering a broad range of research topics, with global reach and spanning incredible time depth. A total of 24 invited symposia (6 podium sessions and 18 poster sessions) included 314 abstracts. Contributed abstract submissions totaled 909. Broken down by sub eld, these include Bioarchaeology (224), Primatology (197), Paleoanthropology (127), Human Biology (108), Functional Anatomy and Tissue Biology (93), Genetics and Genomics (82), Forensics (61) and Education in Biological Anthropology (16). My sincere thanks to everyone who helped organize the 2020 meetings, including review of abstracts. We are immensely grateful to the 49 remarkable and dedicated members of our Program Committee, who conducted and completed reviews thoughtfully, thoroughly, and expeditiously. Thanks are due to our extraordinary business partners, Lori Strong and her team (from Burk & Associates), as well as Ed Hagen (our webmaster, app developer, and member of the Los Angeles Advance Team). We also thank the Los Angeles Advance Team. Our program assistant, Kathleen McGuire, has been a tremendous help, as have the Of cers and other members of the Executive Committee. Special thanks to Leslie Aiello and Anne Grauer for aiding production of our annual meetings in many ways. Finally, we extend our most sincere thanks to the Local Arrangements Committee, Drs. Kristi Lewton and Stephanie Meredith.
Paratethys, the lost sea of central Eurasia, was an anoxic giant during Oligoceneearly Miocene (M... more Paratethys, the lost sea of central Eurasia, was an anoxic giant during Oligoceneearly Miocene (Maikop Series) times. With a size matching the modern-day Mediterranean Sea and a history of anoxic conditions that lasted for over 20 Myrs, the eastern part of this realm (Black Sea-Caspian Sea domain) holds key records for understanding the build-up, maintenance and collapse of anoxia in marginal seas. Here, we show that the collapse of anoxic Maikop conditions was caused by middle Miocene paleogeographic changes in the Paratethys gateway configuration, when a mid-Langhian (Badenian-Tarkhanian) transgression flooded and oxygenated the Eastern Paratethys. We present an integrated magneto-biostratigraphic framework for the early Middle Miocene (Tarkhanian-Chokrakian-Karaganian regional stages) of the Eastern Paratethys and date the lithological transition from anoxic black shales of the Maikop Series to fossiliferous marine marls and limestones of the regional Tarkhanian stage. For this purpose, we selected two long and time-equivalent
Marine gateways prove to be important factors for changes in the ecology and biochemistry of marg... more Marine gateways prove to be important factors for changes in the ecology and biochemistry of marginal seas. Changes in gateway configuration played a dominant role in the Middle Miocene paleogeographic evolution of the Paratethys sea that covered Central Eurasia. Here, we focus on the connection between the Central (CP) and Eastern Paratethys (EP) to understand the paleoenvironmental changes caused by the evolution of this marine gateway. We first construct an integrated magneto-biostratigraphic framework for the late Langhian-Serravallian (Chokrakian-Karaganian-Konkian-Volhynian) sedimentary record of the eastern domain, which allows a correlation to the well-dated successions west of the gateway. The magnetobiostratigraphic results from the Zelensky-Panagia section on the Black Sea coast of Russia show that the Chokrakian/Karaganian boundary has an age of 13.8 Ma, the Karaganian/Konkian boundary is dated at 13.4 Ma, and the Konkian/Volhynian boundary at 12.65 Ma. We identify three major phases on gateway functioning that are reflected in specific environmental changes. During the Karaganian, the EP turned into a lake-sea that supplied a unidirectional flow of low-salinity waters to the west, where the CP sea experienced its Badenian Salinity Crisis. This configuration is remarkably similar to the Mediterranean during its Messinian Salinity Crisis. The second phase is marked by a marine transgression from the west, reinstalling open-marine conditions in the CP and causing marine incursions in the EP
Changing sediment supply during glacial-interglacial intervals in the North Atlantic revealed by particle size characterization and environmental magnetism
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