Geology of the East Siberian Sea, Russian Arctic, from seismic images: Structures, evolution, and implications for the evolution of the Arctic Ocean Basin

The marine molluscan fauna of the Prince Creek Formation near Ocean Point, northern Alaska, is of Danian age. It is the only diverse and abundant Danian molluscan fauna known from the Arctic Ocean realm, and is the first evidence for an indigenous Paleocene shallow-water biota within a discrete Arctic Ocean Basin faunal province.A high percentage of endemic species, and two endemic genera, emphasize the degree to which the Arctic Ocean was geographically isolated from the world ocean during the earliest Tertiary. Many of the well-preserved Ocean Point mollusks, however, also occur in Danian faunas of the North American Western Interior, the Canadian Arctic Islands, Svalbard, and northwestern Europe, and are the basis for relating this Arctic Ocean fauna to that of the Danian world ocean.The Arctic Ocean was a Danian refugium for some genera that became extinct elsewhere during the Jurassic and Cretaceous. At the same time, this nearly landlocked ocean fostered the evolution of new taxa that later in the Paleogene migrated into the world ocean by way of the northeastern Atlantic. The first Cenozoic occurrences are reported for the bivalves Integricardium (Integricardium), Oxytoma (Hypoxytoma), Placunopsis, Tancredia (Tancredia), and Tellinimera, and the oldest Cenozoic records given for the bivalves Gari (Garum), Neilo, and Yoldia (Cnesterium). Among the 25 species in the molluscan fauna are four new gastropod species, Amauropsis fetteri, Ellipsoscapha sohli, Mathilda (Fimbriatella) amundseni, and Polinices (Euspira) repenningi, two new bivalve genera, Arcticlam and Mytilon, and 15 new bivalve species, Arcticlam nanseni, Corbula (Caryocorbula) betsyae, Crenella kannoi, Cyrtodaria katieae, Gari (Garum) brouwersae, Integricardium (Integricardium) keenae, Mytilon theresae, Neilo gryci, Nucula (Nucula) micheleae, Nuculana (Jupiteria) moriyai, Oxytoma (Hypoxytoma) hargrovei, Placunopsis rothi, Tancredia (Tancredia) slavichi, Tellinimera kauffmani, and Yoldia (Cnesterium) gladenkovi.

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A seismic and gravity profile across the Arctic Ocean Basin

Tectonophysics ◽

10.1016/0040-1951(77)90036-1 ◽

1977 ◽

Vol 37 (1-3) ◽

pp. 1-24 ◽

Cited By ~ 43

Author(s):

Ned A Ostenso ◽

Richard J Wold

Keyword(s):

Arctic Ocean ◽

Ocean Basin ◽

The Arctic ◽

The Arctic Ocean ◽

Gravity Profile

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Accurate measurements of atmospheric carbon dioxide and methane mole fractions at the Siberian coastal site Ambarchik

10.5194/amt-2018-325 ◽

2018 ◽

Cited By ~ 1

Author(s):

Friedemann Reum ◽

Mathias Göckede ◽

Jost V. Lavric ◽

Olaf Kolle ◽

Sergey Zimov ◽

...

Keyword(s):

Arctic Ocean ◽

Atmospheric Carbon Dioxide ◽

Monitoring Network ◽

The Arctic ◽

Data Quality Control ◽

In Situ Data ◽

Northeastern Siberia ◽

East Siberian Sea ◽

The Arctic Ocean ◽

Atmospheric Carbon

Abstract. Sparse data coverage in the Arctic hampers our understanding of its carbon cycle dynamics and our predictions of the fate of its vast carbon reservoirs in a changing climate. In this paper, we present accurate measurements of atmospheric CO2 and CH4 dry air mole fractions at the new atmospheric carbon observation station Ambarchik, which closes a large gap in the atmospheric trace gas monitoring network in northeastern Siberia. The site, operational since August 2014, is located near the delta of the Kolyma River at the coast of the Arctic Ocean. Data quality control of CO2 and CH4 measurements includes frequent calibrations traced to WMO scales, employment of a novel water vapor correction, an algorithm to detect influence of local polluters, and meteorological measurements that enable data selection. The available CO2 and CH4 record was characterized in comparison with in situ data from Barrow, Alaska. A footprint analysis reveals that the station is sensitive to signals from the East Siberian Sea, as well as northeast Siberian tundra and taiga regions. This makes data from Ambarchik highly valuable for inverse modeling studies aimed at constraining carbon budgets within the pan-Arctic domain, as well as for regional studies focusing on Siberia and the adjacent shelf areas of the Arctic Ocean.

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The age of the Kap Washington Group volcanics, North Greenland

Bulletin of the Geological Society of Denmark ◽

10.37570/bgsd-1982-31-04 ◽

1982 ◽

Vol 31 ◽

pp. 49-55

Author(s):

O. Larsen

Keyword(s):

Arctic Ocean ◽

Late Cretaceous ◽

Volcanic Activity ◽

Coastal Region ◽

Ocean Basin ◽

The Arctic ◽

Fossil Plant ◽

Plant Remains ◽

The Arctic Ocean ◽

North Greenland

The Kap Washington Group of peralkaline volcanics is exposed along the coast of North Greenland at 40°W. This coastal region is intruded by numerous NNE-NW-trending dolerite dykes of alkaline affinity. The volcanics and their basic intrusive counterparts appear to be related to the initial rifting in the Arctic Ocean basin. The timing of this rifting may be supported by accurate dating of the associated volcanic activity. An improved Rb/Sr age of 64±3 million years (i.e. approximately at the Cretaceous-Tertiary boundary) has been determined on rhyolitic lavas collected at Kap Kane, probably near the top of the volcanic sequence. The extrusive volcanic activity probably started already in late Cretaceous time, as indicated by fossil plant remains, found in sediments interbedded with the lavas on Lockwood 0.

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Circulation timescales of Atlantic Waters in the Arctic Ocean determined from anthropogenic radionuclides

10.5194/os-2020-82 ◽

2020 ◽

Author(s):

Anne-Marie Wefing ◽

Núria Casacuberta ◽

Marcus Christl ◽

Nicolas Gruber ◽

John N. Smith

Keyword(s):

Arctic Ocean ◽

Ocean Basin ◽

The Arctic ◽

Fram Strait ◽

Anthropogenic Radionuclides ◽

Artificial Radionuclides ◽

East Greenland Current ◽

The Arctic Ocean ◽

Lateral Mixing ◽

Binary Mixing

Abstract. The inflow of Atlantic Waters to the Arctic Ocean is a crucial determinant for the future trajectory of this ocean basin with regard to warming, loss of sea-ice and ocean acidification. Yet many details of the fate and circulation of these waters within the Arctic remain unclear. Here, we use the two long-lived artificial radionuclides 129I and 236U together with two tracer age models to constrain the pathways and circulation times of Atlantic waters in the surface and in the mid-depth Atlantic layer (250–800 m depth). We thereby benefit from the unique time-dependent tagging of Atlantic waters by these two isotopes. In the surface layer, a binary mixing model yields tracer ages of Atlantic Waters between 9–16 years in the Amundsen Basin, 12–17 years in the Fram Strait (East Greenland Current) and up to 20 years in the Canada Basin, reflecting the pathways of Atlantic Waters through the Arctic and their exiting through Fram Strait. In the mid-depth Atlantic layer (250 to 800 m), the transit time distribution (TTD) model yields mean ages in the central Arctic ranging between 15 and 65 years, while the mode ages representing the most probable ages of the TTD range between 2 and 30 years. The estimated mean ages are overall in good agreement with previous studies using artificial radionuclides or ventilation tracers. Although we find the overall flow to be dominated by advection, the shift of the mode age towards a younger age compared to the mean age reflects also the presence of a substantial amount of lateral mixing. For applications interested in how fast signals are transported into the Arctic's interior, the mode age appears to be a suitable measure. The short mode ages obtained in this study suggest that changes in the properties of Atlantic Waters will quickly spread through the Arctic Ocean and can lead to relatively rapid changes throughout the upper water column in future years.

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Circulation timescales of Atlantic Water in the Arctic Ocean determined from anthropogenic radionuclides

Ocean Science ◽

10.5194/os-17-111-2021 ◽

2021 ◽

Vol 17 (1) ◽

pp. 111-129

Author(s):

Anne-Marie Wefing ◽

Núria Casacuberta ◽

Marcus Christl ◽

Nicolas Gruber ◽

John N. Smith

Keyword(s):

Arctic Ocean ◽

Atlantic Water ◽

Ocean Basin ◽

The Arctic ◽

Fram Strait ◽

Anthropogenic Radionuclides ◽

East Greenland Current ◽

The Arctic Ocean ◽

Lateral Mixing ◽

Binary Mixing

Abstract. The inflow of Atlantic Water to the Arctic Ocean is a crucial determinant for the future trajectory of this ocean basin with regard to warming, loss of sea ice, and ocean acidification. Yet many details of the fate and circulation of these waters within the Arctic remain unclear. Here, we use the two long-lived anthropogenic radionuclides 129I and 236U together with two age models to constrain the pathways and circulation times of Atlantic Water in the surface (10–35 m depth) and in the mid-depth Atlantic layer (250–800 m depth). We thereby benefit from the unique time-dependent tagging of Atlantic Water by these two isotopes. In the surface layer, a binary mixing model yields tracer ages of Atlantic Water between 9–16 years in the Amundsen Basin, 12–17 years in the Fram Strait (East Greenland Current), and up to 20 years in the Canada Basin, reflecting the pathways of Atlantic Water through the Arctic and their exiting through the Fram Strait. In the mid-depth Atlantic layer (250–800 m), the transit time distribution (TTD) model yields mean ages in the central Arctic ranging between 15 and 55 years, while the mode ages representing the most probable ages of the TTD range between 3 and 30 years. The estimated mean ages are overall in good agreement with previous studies using artificial radionuclides or ventilation tracers. Although we find the overall flow to be dominated by advection, the shift in the mode age towards a younger age compared to the mean age also reflects the presence of a substantial amount of lateral mixing. For applications interested in how fast signals are transported into the Arctic's interior, the mode age appears to be a suitable measure. The short mode ages obtained in this study suggest that changes in the properties of Atlantic Water will quickly spread through the Arctic Ocean and can lead to relatively rapid changes throughout the upper water column in future years.

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On the circulation, water mass distribution, and nutrient concentrations of the western Chukchi Sea

Ocean Science ◽

10.5194/os-18-29-2022 ◽

2022 ◽

Vol 18 (1) ◽

pp. 29-49

Author(s):

Jaclyn Clement Kinney ◽

Karen M. Assmann ◽

Wieslaw Maslowski ◽

Göran Björk ◽

Martin Jakobsson ◽

...

Keyword(s):

Numerical Modelling ◽

Arctic Ocean ◽

Dissolved Inorganic Carbon ◽

Chukchi Sea ◽

The Arctic ◽

Sediment Surface ◽

Nutrient Concentrations ◽

Bering Strait ◽

East Siberian Sea ◽

The Arctic Ocean

Abstract. Substantial amounts of nutrients and carbon enter the Arctic Ocean from the Pacific Ocean through the Bering Strait, distributed over three main pathways. Water with low salinities and nutrient concentrations takes an eastern route along the Alaskan coast, as Alaskan Coastal Water. A central pathway exhibits intermediate salinity and nutrient concentrations, while the most nutrient-rich water enters the Bering Strait on its western side. Towards the Arctic Ocean, the flow of these water masses is subject to strong topographic steering within the Chukchi Sea with volume transport modulated by the wind field. In this contribution, we use data from several sections crossing Herald Canyon collected in 2008 and 2014 together with numerical modelling to investigate the circulation and transport in the western part of the Chukchi Sea. We find that a substantial fraction of water from the Chukchi Sea enters the East Siberian Sea south of Wrangel Island and circulates in an anticyclonic direction around the island. This water then contributes to the high-nutrient waters of Herald Canyon. The bottom of the canyon has the highest nutrient concentrations, likely as a result of addition from the degradation of organic matter at the sediment surface in the East Siberian Sea. The flux of nutrients (nitrate, phosphate, and silicate) and dissolved inorganic carbon in Bering Summer Water and Winter Water is computed by combining hydrographic and nutrient observations with geostrophic transport referenced to lowered acoustic Doppler current profiler (LADCP) and surface drift data. Even if there are some general similarities between the years, there are differences in both the temperature–salinity and nutrient characteristics. To assess these differences, and also to get a wider temporal and spatial view, numerical modelling results are applied. According to model results, high-frequency variability dominates the flow in Herald Canyon. This leads us to conclude that this region needs to be monitored over a longer time frame to deduce the temporal variability and potential trends.

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