A lithosphere-scale structural model of the Barents Sea and Kara Sea  region

Abstract. We introduce a regional 3-D structural model of the Barents Sea and Kara Sea region which is the first to combine information on the sediments and the crystalline crust as well as the configuration of the lithospheric mantle. Therefore, we have integrated all available geological and geophysical data, including interpreted seismic refraction and reflection data, seismological data, geological maps and previously published 3-D models into one consistent model. This model resolves four major megasequence boundaries (earliest Eocene, mid-Cretaceous, mid-Jurassic and mid-Permian) the top crystalline crust, the Moho and a newly calculated lithosphere–asthenosphere boundary (LAB). The thickness distributions of the corresponding main megasequences delineate five major subdomains (the northern Kara Sea, the southern Kara Sea, the eastern Barents Sea, the western Barents Sea and the oceanic domain comprising the Norwegian–Greenland Sea and the Eurasia Basin). Relating the subsidence histories of these subdomains to the structure of the deeper crust and lithosphere sheds new light on possible causative basin forming mechanisms that we discuss. The depth configuration of the newly calculated LAB and the seismic velocity configuration of the upper mantle correlate with the younger history of this region. The western Barents Sea is underlain by a thinned lithosphere (80 km) resulting from multiple Phanerozoic rifting phases and/or the opening of the NE Atlantic from Paleocene/Eocene times on. Notably, the northwestern Barents Sea and Svalbard are underlain by thinnest continental lithosphere (60 km) and a low-velocity/hot upper mantle that correlates spatially with a region where late Cenozoic uplift was strongest. As opposed to this, the eastern Barents Sea is underlain by a thicker lithosphere (~ 110–150 km) and a high-velocity/density anomaly in the lithospheric mantle. This anomaly, in turn, correlates with an area where only little late Cenozoic uplift/erosion was observed.

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A lithosphere-scale structural model of the Barents Sea and Kara Sea region

Solid Earth Discussions ◽

10.5194/sed-6-1579-2014 ◽

2014 ◽

Vol 6 (2) ◽

pp. 1579-1624 ◽

Cited By ~ 2

Author(s):

P. Klitzke ◽

J. I. Faleide ◽

M. Scheck-Wenderoth ◽

J. Sippel

Keyword(s):

Structural Model ◽

Barents Sea ◽

Kara Sea ◽

High Density ◽

The South ◽

The West ◽

Density Anomaly ◽

The Barents Sea ◽

Early Cenozoic ◽

Oceanic Domain

Abstract. The Barents Sea and Kara Sea region as part of the European Arctic shelf, is geologically situated between the Proterozoic East-European Craton in the south and early Cenozoic passive margins in the north and the west. Proven and inferred hydrocarbon resources encouraged numerous industrial and academic studies in the last decades which brought along a wide spectrum of geological and geophysical data. By evaluating all available interpreted seismic refraction and reflection data, geological maps and previously published 3-D-models, we were able to develop a new lithosphere-scale 3-D-structural model for the greater Barents Sea and Kara Sea region. The sedimentary part of the model resolves four major megasequence boundaries (earliest Eocene, mid-Cretaceous, mid-Jurassic and mid-Permian). Downwards, the 3-D-structural model is complemented by the top crystalline crust, the Moho and a newly calculated lithosphere-asthenosphere boundary (LAB). The thickness distribution of the main megasequences delineates five major subdomains differentiating the region (the northern Kara Sea, the southern Kara Sea, the eastern Barents Sea, the western Barents Sea and the oceanic domain comprising the Norwegian-Greenland Sea and the Eurasia Basin). The vertical resolution of five sedimentary megasequences allows comparing for the first time the subsidence history of these domains directly. Relating the sedimentary structures with the deeper crustal/lithospheric configuration sheds some light on possible causative basin forming mechanisms that we discuss. The newly calculated LAB deepens from the typically shallow oceanic domain in three major steps beneath the Barents and Kara shelves towards the West-Siberian Basin in the east. Thereby, we relate the shallow continental LAB and slow/hot mantle beneath the southwestern Barents Sea with the formation of deep Paleozoic/Mesozoic rift basins. Thinnest continental lithosphere is observed beneath Svalbard and the NW Barents Sea where no Mesozoic/early Cenozoic rifting has occurred but strongest Cenozoic uplift and volcanism since Miocene times. The East Barents Sea Basin is underlain by a LAB at moderate depths and a high-density anomaly in the lithospheric mantle which follows the basin geometry and a domain where the least amount of late Cenozoic uplift/erosion is observed. Strikingly, this high-density anomaly is not present beneath the adjacent southern Kara Sea. Both basins share a strong Mesozoic subsidence phase whereby the main subsidence phase is younger in the South Kara Sea Basin.

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Climate change impacts on sea–air fluxes of CO<sub>2</sub> in three Arctic seas: a sensitivity study using Earth observation

Biogeosciences ◽

10.5194/bg-10-8109-2013 ◽

2013 ◽

Vol 10 (12) ◽

pp. 8109-8128 ◽

Cited By ~ 17

Author(s):

P. E. Land ◽

J. D. Shutler ◽

R. D. Cowling ◽

D. K. Woolf ◽

P. Walker ◽

...

Keyword(s):

Climate Change ◽

Sea Ice ◽

Barents Sea ◽

Earth Observation ◽

Kara Sea ◽

Sink Strength ◽

Arctic Seas ◽

The Barents Sea ◽

Co2 Sink ◽

Positive Effect

Abstract. We applied coincident Earth observation data collected during 2008 and 2009 from multiple sensors (RA2, AATSR and MERIS, mounted on the European Space Agency satellite Envisat) to characterise environmental conditions and integrated sea–air fluxes of CO2 in three Arctic seas (Greenland, Barents, Kara). We assessed net CO2 sink sensitivity due to changes in temperature, salinity and sea ice duration arising from future climate scenarios. During the study period the Greenland and Barents seas were net sinks for atmospheric CO2, with integrated sea–air fluxes of −36 ± 14 and −11 ± 5 Tg C yr−1, respectively, and the Kara Sea was a weak net CO2 source with an integrated sea–air flux of +2.2 ± 1.4 Tg C yr−1. The combined integrated CO2 sea–air flux from all three was −45 ± 18 Tg C yr−1. In a sensitivity analysis we varied temperature, salinity and sea ice duration. Variations in temperature and salinity led to modification of the transfer velocity, solubility and partial pressure of CO2 taking into account the resultant variations in alkalinity and dissolved organic carbon (DOC). Our results showed that warming had a strong positive effect on the annual integrated sea–air flux of CO2 (i.e. reducing the sink), freshening had a strong negative effect and reduced sea ice duration had a small but measurable positive effect. In the climate change scenario examined, the effects of warming in just over a decade of climate change up to 2020 outweighed the combined effects of freshening and reduced sea ice duration. Collectively these effects gave an integrated sea–air flux change of +4.0 Tg C in the Greenland Sea, +6.0 Tg C in the Barents Sea and +1.7 Tg C in the Kara Sea, reducing the Greenland and Barents sinks by 11% and 53%, respectively, and increasing the weak Kara Sea source by 81%. Overall, the regional integrated flux changed by +11.7 Tg C, which is a 26% reduction in the regional sink. In terms of CO2 sink strength, we conclude that the Barents Sea is the most susceptible of the three regions to the climate changes examined. Our results imply that the region will cease to be a net CO2 sink in the 2050s.

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Late Cenozoic Stratigraphy and Paleoceanology of the Barents Sea

The Arctic Seas ◽

10.1007/978-1-4613-0677-1_25 ◽

1989 ◽

pp. 721-727 ◽

Cited By ~ 6

Author(s):

V. S. Zarkhidze ◽

Yu. G. Samoilovich

Keyword(s):

Barents Sea ◽

Late Cenozoic ◽

The Barents Sea

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Climate change impacts on sea-air fluxes of CO<sub>2</sub> in three Arctic seas: a sensitivity study using earth observation

Biogeosciences Discussions ◽

10.5194/bgd-9-12377-2012 ◽

2012 ◽

Vol 9 (9) ◽

pp. 12377-12432 ◽

Cited By ~ 1

Author(s):

P. E. Land ◽

J. D. Shutler ◽

R. D. Cowling ◽

D. K. Woolf ◽

P. Walker ◽

...

Keyword(s):

Climate Change ◽

Sea Ice ◽

Barents Sea ◽

Earth Observation ◽

Kara Sea ◽

Sink Strength ◽

Arctic Seas ◽

The Barents Sea ◽

Co2 Sink ◽

Positive Effect

Abstract. During 2008 and 2009 we applied coincident Earth observation data collected from multiple sensors (RA2, AATSR and MERIS, mounted on the European Space Agency satellite Envisat) to characterise environmental conditions and net sea-air fluxes of CO2 in three Arctic seas (Greenland, Barents, Kara) to assess net CO2 sink sensitivity due to changes in temperature, salinity and sea ice duration arising from future climate scenarios. During the study period the Greenland and Barents Seas were net sinks for atmospheric CO2, with sea-air fluxes of −34±13 and −13±6 Tg C yr−1, respectively and the Kara Sea was a weak net CO2 source with a sea-air flux of +1.5±1.1 Tg C yr−1. The combined net CO2 sea-air flux from all three was −45±18 Tg C yr−1. In a sensitivity analysis we varied temperature, salinity and sea ice duration. Variations in temperature and salinity led to modification of the transfer velocity, solubility and partial pressure of CO2 taking into account the resultant variations in alkalinity and dissolved organic carbon (DOC). Our results showed that warming had a strong positive effect on the annual net sea-air flux of CO2 (i.e. reducing the sink), freshening had a strong negative effect and reduced sea ice duration had a small but measurable positive effect. In the climate change scenario examined, the effects of warming in just over a decade of climate change up to 2020 outweighed the combined effects of freshening and reduced sea ice duration. Collectively these effects gave a net sea-air flux change of +3.5 Tg C in the Greenland Sea, +5.5 Tg C in the Barents Sea and +1.4 Tg C in the Kara Sea, reducing the Greenland and Barents sinks by 10% and 50% respectively, and increasing the weak Kara Sea source by 64%. Overall, the regional flux changed by +10.4 Tg C, reducing the regional sink by 23%. In terms of CO2 sink strength we conclude that the Barents Sea is the most susceptible of the three regions to the climate changes examined. Our results imply that the region will cease to be a net CO2 sink by 2060.

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Quaternary sodic and potassic intraplate volcanism in northeast China controlled by the underlying heterogeneous lithospheric structures

Geology ◽

10.1130/g48932.1 ◽

2021 ◽

Author(s):

Xingli Fan ◽

Qi-Fu Chen ◽

Yinshuang Ai ◽

Ling Chen ◽

Mingming Jiang ◽

...

Keyword(s):

Upper Mantle ◽

Lithospheric Mantle ◽

Northeast China ◽

Velocity Structure ◽

Seismic Velocity ◽

Subcontinental Lithospheric Mantle ◽

Seismic Velocities ◽

S Wave ◽

Crust And Upper Mantle ◽

Potassic Volcanism

The origin and mantle dynamics of the Quaternary intraplate sodic and potassic volcanism in northeast China have long been intensely debated. We present a high-resolution, three-dimensional (3-D) crust and upper-mantle S-wave velocity (Vs) model of northeast China by combining ambient noise and earthquake two-plane wave tomography based on unprecedented regional dense seismic arrays. Our seismic images highlight a strong correlation between the basalt geochemistry and upper-mantle seismic velocity structure: Sodic volcanoes are all characterized by prominent low seismic velocities in the uppermost mantle, while potassic volcanoes still possess a normal but thin upper-mantle “lid” depicted by high seismic velocities. Combined with previous petrological and geochemical research findings, we propose that the rarely erupted Quaternary potassic volcanism in northeast China results from the interaction between asthenospheric low-degree melts and the overlying subcontinental lithospheric mantle. In contrast, the more widespread Quaternary sodic volcanism in this region is predominantly sourced from the upwelling asthenosphere without significant overprinting from the subcontinental lithospheric mantle.

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Crustal domains in the Western Barents Sea

Geophysical Journal International ◽

10.1093/gji/ggaa112 ◽

2020 ◽

Vol 221 (3) ◽

pp. 2155-2169

Author(s):

Alexey Shulgin ◽

Jan Inge Faleide ◽

Rolf Mjelde ◽

Asbjørn Breivik ◽

Ritske Huismans

Keyword(s):

Seismic Reflection ◽

Barents Sea ◽

The Body ◽

Gravity Modelling ◽

Southern Boundary ◽

Mafic Intrusions ◽

Crustal Block ◽

The Barents Sea ◽

Crystalline Crust ◽

Regional Gravity

SUMMARY The crustal architecture of the Barents Sea is still enigmatic due to complex evolution during the Timanian and Caledonian orogeny events, further complicated by several rifting episodes. In this study we present the new results on the crustal structure of the Caledonian–Timanian transition zone in the western Barents. We extend the work of Aarseth et al. (2017), by utilizing the seismic tomography approach to model Vp, Vs and Vp/Vs ratio, combined with the reprocessed seismic reflection line, and further complemented with gravity modelling. Based on our models we document in 3-D the position of the Caledonian nappes in the western Barents Sea. We find that the Caledonian domain is characterized by high crustal reflectivity, caused by strong deformation and/or emplacement of mafic intrusions within the crystalline crust. The Timanian domain shows semi-transparent crust with little internal reflectivity, suggesting less deformation. We find, that the eastern branch of the earlier proposed Caledonian suture, cannot be associated with the Caledonian event, but can rather be a relict from the Timanian terrane assemblance, marking one of the crustal microblocks. This crustal block may have an E–W striking southern boundary, along which the Caledonian nappes were offset. A high-velocity/density crustal body, adjacent to the Caledonian–Timanian contact zone, is interpreted as a zone of metamorphosed rocks based on the comparison with global compilations. The orientation of this body correlates with regional gravity maxima zone. Two scenarios for the origin of the body are proposed: mafic emplacement during the Timanian assembly, or massive mafic intrusions associated with the Devonian extension.

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A 3D gravity and thermal model for the Barents Sea and Kara Sea

Tectonophysics ◽

10.1016/j.tecto.2016.04.033 ◽

2016 ◽

Vol 684 ◽

pp. 131-147 ◽

Cited By ~ 12

Author(s):

Peter Klitzke ◽

Judith Sippel ◽

Jan Inge Faleide ◽

Magdalena Scheck-Wenderoth

Keyword(s):

Thermal Model ◽

Barents Sea ◽

Kara Sea ◽

The Barents Sea ◽

3D Gravity

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Aleksandr Stepanovich Kuchin: the Russian who went south with Amundsen

Polar Record ◽

10.1017/s0032247400005647 ◽

1985 ◽

Vol 22 (139) ◽

pp. 401-412 ◽

Cited By ~ 4

Author(s):

William Barr

Keyword(s):

Atlantic Ocean ◽

Barents Sea ◽

Kara Sea ◽

South Pole ◽

Bering Strait ◽

The Barents Sea ◽

Northern Sea Route ◽

Océanographic Survey ◽

The Antarctic ◽

Southern Atlantic Ocean

AbstractAleksandr Stepanovich Kuchin (1888–1912) was already an experienced mariner and oceanographer when Amundsen invited him to join the Fram expedition of 1910–12. Expecting a voyage through the Barents Sea, Kuchin found himself on an expedition to the Antarctic. While Amundsen's sledging parties sought the South Pole, Kuchin remained with the ship, completing an excellent oceanographic survey of the southern Atlantic Ocean. Returning to Russia in 1912 he was recruited, by the geologist and explorer V. A. Rusinov to join a scientific expedition to Svalbard. As deputy leader of the party and captain of Gerkules, the expedition ship, Kuchin played an important role in the Svalbard survey. Then once again found himself heading in an unexpected direction: on completing the Svalbard work, Rusanov decided to attempt the Northern Sea Route to the Bering Strait. Gerkules disappeared and was never seen again; her loss, presumably in the Kara Sea, brought to an untimely end the career of a promising young polar explorer.

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Conditions of formation and forecast of natural reservoirs in clinoform complex of the Lower Cretaceous of the Barents-Kara shelf

Georesursy ◽

10.18599/grs.2019.2.63-79 ◽

2019 ◽

Vol 21 (2) ◽

pp. 63-79

Author(s):

Alina V. Mordasova ◽

Antonina V. Stoupakova ◽

Anna A. Suslova ◽

Daria K. Ershova ◽

Svetlana A. Sidorenko

Keyword(s):

Detailed Analysis ◽

Lower Cretaceous ◽

Oil And Gas ◽

Barents Sea ◽

Kara Sea ◽

Distribution Area ◽

Geological Model ◽

The Barents Sea ◽

Gas Potential ◽

Cretaceous Deposits

Unique Leningradsky and Rusanovsky gascondensate fields in the Barrem-Cenomanian layer are discovered in the Kara Sea. Non-industrial accumulations of oil and gas have been discovered in the Lower Cretaceous sediments of the western part of the Barents Sea shelf. However, the structure and oil and gas potential of the Lower Cretaceous sediments of the Barents-Kara shelf remain unexplored. Based on the seismic-stratigraphic and cyclostratigraphic analysis, a regional geological model of the Lower Cretaceous deposits of the Barents-Kara shelf was created, the distribution area and the main stages of the accumulation of clinoforms were identified. As a result of a detailed analysis of the morphology of clinoform bodies, paleogeographic conditions were restored in the Early Cretaceous and a forecast of the distribution of sandy reservoirs was given

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A mechanism of spring Barents Sea ice effect on the extreme summer droughts in northeastern China

10.21203/rs.3.rs-377893/v1 ◽

2021 ◽

Author(s):

YiBo Du ◽

Jie Zhang ◽

Siwen Zhao ◽

Zhiheng Chen

Keyword(s):

Sea Ice ◽

North Atlantic ◽

Barents Sea ◽

Kara Sea ◽

Northeastern China ◽

Arctic Sea Ice ◽

Extreme Drought ◽

Negative Phase ◽

Vapor Flux ◽

The Barents Sea

Abstract The frequency of extreme drought events in northeastern China (NEC) has increased since the 2000s, and such a decadal anomalous trend may lead to significant stress on agriculture and economic development. The correlation between Arctic sea ice loss in spring and extreme summer droughts over NEC was investigated. The results show that the loss of sea ice over the Barents Sea in spring is associated with extreme droughts and positive height anomalies over NEC in summer. The physical processes include two pathways. First, Arctic ice loss from the Barents Sea to the Kara Sea results in reducing baroclinicity over the ice loss region but increasing baroclinicity over the ice melting region, which is favorable to the wave ridge over northern Europe and negative-phase Summer North Atlantic Oscillation (SNAO). One wave train originates from negative-phase SNAO over North Atlantic–Europe and spreads to central Europe, central Asia, and NEC. Second, another wave motion flux originates from the Barents–Kara Sea propagating eastward, and then disperses southward to NEC. Both wave trains lead to anomalous anticyclonic circulation and westward subtropical high, which favors descending motion and less water vapor flux, thereby contributing to extreme drought.

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