Linking sediment supply variations and tectonic evolution in deep time, source-to-sink systems—The Triassic Greater Barents Sea Basin

Triassic strata in the Greater Barents Sea Basin are important records of geodynamic activity in the surrounding catchments and sediment transport in the Arctic basins. This study is the first attempt to investigate the evolution of these source areas through time. Our analysis of sediment budgets from subsurface data in the Greater Barents Sea Basin and application of the BQART approach to estimate catchment properties shows that (1) during the Lower Triassic, sediment supply was at its peak in the basin and comparable to that of the biggest modern-day river systems, which are supplied by tectonically active orogens; (2) the Middle Triassic sediment load was significantly lower but still comparable to that of the top 10 largest modern rivers; (3) during the Upper Triassic, sediment load increased again in the Carnian; and (4) there is a large mismatch (70%) between the modeled and estimated sediment load of the Carnian. These results are consistent with the Triassic Greater Barents Sea Basin succession being deposited under the influence of the largest volcanic event ever at the Permian-Triassic boundary (Siberian Traps) and concurrent with the climatic changes of the Carnian Pluvial Event and the final stages of the Northern Ural orogeny. They also provide a better understanding of geodynamic impacts on sedimentary systems and improve our knowledge of continental-scale sediment transport. Finally, the study demonstrates bypass of sediment from the Ural Mountains and West Siberia into the adjacent Arctic Sverdrup, Chukotka, and Alaska Basins in Late Carnian and Late Norian time.

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Global carbon isotope signal in the Middle Triassic on Svalbard

10.5194/egusphere-egu21-15701 ◽

2021 ◽

Author(s):

Victoria S. Engelschiøn ◽

Øyvind Hammer ◽

Fredrik Wesenlund ◽

Jørn H. Hurum ◽

Atle Mørk

Keyword(s):

Carbon Isotope ◽

Depositional Environment ◽

Middle Triassic ◽

Barents Sea ◽

Water Productivity ◽

Sedimentary Environment ◽

The Arctic ◽

Late Triassic ◽

Triassic Boundary ◽

Thin Sections

Several carbon isotope curves were recently published for the Early and Middle Triassic in Tethys. Recent work has also been done on the Early Triassic of Svalbard, but not yet for the Middle Triassic. This work is the first to measure &#948;13C for different Middle Triassic localities on Svalbard, which was then part of the Boreal Ocean on northern Pangea. Our aim is to understand the controls on the Svalbard carbon isotope curve and to place them in a global setting.Correlating Triassic rocks around the world is interesting for several reasons. The Triassic Period was a tumultuous time for life, and the Arctic archipelago of Svalbard has shown to be an important locality to understand the early radiation of marine vertebrates in the Triassic. Much effort is also made to understand the development of the Barents Sea through Svalbard&#8217;s geology.Carbon isotope curves are controlled by depositional environment and global fluctuations. Global factors such as the carbon cycle control the long-term carbon isotopic compositions, while short-term fluctuations may reflect the origin of organic materials in the sediment (e.g. algal or terrestrial matter), stratification of the water column, and/or surface water productivity. Carbon isotopes can therefore be useful to understand the depositional environment and to correlate time-equivalent rocks globally.The dataset was collected through three seasons of fieldwork in Svalbard with localities from the islands Spitsbergen, Edge&#248;ya and Bj&#248;rn&#248;ya. Detailed stratigraphic sampling has resulted in high-resolution &#948;13C curves. These show three strong transitions; 1) on the boundary between the Early and Middle Triassic, 2) in the middle of the formation and 3) at the Middle and Late Triassic boundary. Several Tethyan localities show a possibly similar Early-Middle Triassic signal. Current work in progress is sedimentological analysis by thin sections and X-ray fluorescence spectroscopy (XRF) to further understand the sedimentary environment.

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Provenance of Pennsylvanian–Permian sedimentary rocks associated with the Ancestral Rocky Mountains orogeny in southwestern Laurentia: Implications for continental-scale Laurentian sediment transport systems

Lithosphere ◽

10.1130/l1115.1 ◽

2020 ◽

Vol 12 (1) ◽

pp. 88-121 ◽

Cited By ~ 4

Author(s):

Ryan J. Leary ◽

Paul Umhoefer ◽

M. Elliot Smith ◽

Tyson M. Smith ◽

Joel E. Saylor ◽

...

Keyword(s):

Sediment Transport ◽

Rocky Mountains ◽

Detrital Zircon ◽

Rocky Mountain ◽

Sedimentary Basins ◽

The Arctic ◽

Transport Systems ◽

Published Data ◽

Transport Pathways ◽

Continental Scale

Abstract The Ancestral Rocky Mountains system consists of a series of basement-cored uplifts and associated sedimentary basins that formed in southwestern Laurentia during Early Pennsylvanian–middle Permian time. This system was originally recognized by aprons of coarse, arkosic sandstone and conglomerate within the Paradox, Eagle, and Denver Basins, which surround the Front Range and Uncompahgre basement uplifts. However, substantial portions of Ancestral Rocky Mountain–adjacent basins are filled with carbonate or fine-grained quartzose material that is distinct from proximal arkosic rocks, and detrital zircon data from basins adjacent to the Ancestral Rocky Mountains have been interpreted to indicate that a substantial proportion of their clastic sediment was sourced from the Appalachian and/or Arctic orogenic belts and transported over long distances across Laurentia into Ancestral Rocky Mountain basins. In this study, we present new U-Pb detrital zircon data from 72 samples from strata within the Denver Basin, Eagle Basin, Paradox Basin, northern Arizona shelf, Pedregosa Basin, and Keeler–Lone Pine Basin spanning ∼50 m.y. and compare these to published data from 241 samples from across Laurentia. Traditional visual comparison and inverse modeling methods map sediment transport pathways within the Ancestral Rocky Mountains system and indicate that proximal basins were filled with detritus eroded from nearby basement uplifts, whereas distal portions of these basins were filled with a mix of local sediment and sediment derived from marginal Laurentian sources including the Arctic Ellesmerian orogen and possibly the northern Appalachian orogen. This sediment was transported to southwestern Laurentia via a ca. 2,000-km-long longshore and aeolian system analogous to the modern Namibian coast. Deformation of the Ancestral Rocky Mountains slowed in Permian time, reducing basinal accommodation and allowing marginal clastic sources to overwhelm the system.

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Impact of climatic step-changes on source-to-sink systems: Petrographic changes across the Permian-Triassic changes on the Finnmark Platform, Barents Sea, N Norway

10.5194/egusphere-egu21-9296 ◽

2021 ◽

Author(s):

Melanie Kling ◽

Hallgeir Sirevaag ◽

Emmanuelle Pucéat ◽

Christian Haug Eide

Keyword(s):

Barents Sea ◽

Lower Triassic ◽

Climatic Changes ◽

Depositional Environments ◽

Large Igneous Province ◽

Upper Permian ◽

Triassic Boundary ◽

Source To Sink ◽

Igneous Province

The emplacement of the Siberian Traps Large Igneous Province around the Permian&#8211;Triassic boundary significantly affected both climate and depositional environments across the world. Known long term consequences of this event are (I) global warming, (II) increased continental weathering, (III) oceanic stagnation and acidification and (IV) mass extinction. These effects have the potential to strongly alter signals from source-to-sink systems in terms of petrography, sediment volumes and geochemistry. The Barents Sea Basin is an excellent area to investigate the response of source-to-sink systems to such climatic changes because it contains a continuous record of sediments deposited before, during and after the Permian-Triassic event, and because this interval is sampled in several exploration wells.The goal of this project is to investigate how the Triassic climatic changes were expressed in source-to-sink systems, mainly using techniques such as facies analysis, petrograpy, mudstone geochemistry and sediment volumes. Herein we present preliminary results mainly from sandstone petrology. On the Finnmark Plattform, the upper Permian strata of the R&#248;ye Formation contains spiculitic mudstones and limestones with sparse sandstones. These are overlain by mudstones, interbedded turbidites and prograding deltas of the Lower Triassic. In order to determine how the signal from the catchment changed to the great climatic changes, it is of high importance to examine changes within provenance and sediment volumes across the P-T boundary.I wish to give this presentation as a poster

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Summer phytoplankton of the northern Barents Sea (75–80º N)

Hydrosphere Еcology (Экология гидросферы) ◽

10.33624/2587-9367-2019-2(4)-8-19 ◽

2019 ◽

pp. 8-19

Author(s):

Larisa A. Pautova ◽

Vladimir A. Silkin ◽

Marina D. Kravchishina ◽

Valeriy G. Yakubenko ◽

Anna L. Chultsova

Keyword(s):

Barents Sea ◽

Weighted Average ◽

Arctic Basin ◽

High Arctic ◽

Alexandrium Tamarense ◽

Warm Water ◽

The Arctic ◽

Absolute Maximum ◽

Deep Trench ◽

Maximum Biomass

The structure of the summer planktonic communities of the Northern part of the Barents sea in the first half of August 2017 were studied. In the sea-ice melting area, the average phytoplankton biomass producing upper 50-meter layer of water reached values levels of eutrophic waters (up to 2.1 g/m3). Phytoplankton was presented by diatoms of the genera Thalassiosira and Eucampia. Maximum biomass recorded at depths of 22–52 m, the absolute maximum biomass community (5,0 g/m3) marked on the horizon of 45 m (station 5558), located at the outlet of the deep trench Franz Victoria near the West coast of the archipelago Franz Josef Land. In ice-free waters, phytoplankton abundance was low, and the weighted average biomass (8.0 mg/m3 – 123.1 mg/m3) corresponded to oligotrophic waters and lower mesotrophic waters. In the upper layers of the water population abundance was dominated by small flagellates and picoplankton from, biomass – Arctic dinoflagellates (Gymnodinium spp.) and cold Atlantic complexes (Gyrodinium lachryma, Alexandrium tamarense, Dinophysis norvegica). The proportion of Atlantic species in phytoplankton reached 75%. The representatives of warm-water Atlantic complex (Emiliania huxleyi, Rhizosolenia hebetata f. semispina, Ceratium horridum) were recorded up to 80º N, as indicators of the penetration of warm Atlantic waters into the Arctic basin. The presence of oceanic Atlantic species as warm-water and cold systems in the high Arctic indicates the strengthening of processes of “atlantificacion” in the region.

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Using Fluvial Sediment Transport Equilibrium to Drive Stream Restoration and Establish Sediment Load Reduction Targets

Proceedings of the Water Environment Federation ◽

10.2175/193864716819714933 ◽

2016 ◽

Vol 2016 (6) ◽

pp. 1224-1237

Author(s):

Scott Dierks ◽

Scott Isenberg

Keyword(s):

Sediment Transport ◽

Stream Restoration ◽

Sediment Load ◽

Load Reduction ◽

Fluvial Sediment ◽

Fluvial Sediment Transport

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Phylogeography of the Brittle Star Ophiura sarsii Lütken, 1855 (Echinodermata: Ophiuroidea) from the Barents Sea and East Atlantic

Diversity ◽

10.3390/d13020040 ◽

2021 ◽

Vol 13 (2) ◽

pp. 40

Author(s):

Evgeny Genelt-Yanovskiy ◽

Yixuan Li ◽

Ekaterina Stratanenko ◽

Natalia Zhuravleva ◽

Natalia Strelkova ◽

...

Keyword(s):

Genetic Diversity ◽

Barents Sea ◽

Haplotype Diversity ◽

Brittle Star ◽

The Arctic ◽

Coi Gene ◽

High Genetic Diversity ◽

Svalbard Archipelago ◽

Mitochondrial Coi ◽

The Barents Sea

Ophiura sarsii is a common brittle star species across the Arctic and Sub-Arctic regions of the Atlantic and the Pacific oceans. Ophiurasarsii is among the dominant echinoderms in the Barents Sea. We studied the genetic diversity of O.sarsii by sequencing the 548 bp fragment of the mitochondrial COI gene. Ophiurasarsii demonstrated high genetic diversity in the Barents Sea. Both major Atlantic mtDNA lineages were present in the Barents Sea and were evenly distributed between the northern waters around Svalbard archipelago and the southern part near Murmansk coast of Kola Peninsula. Both regions, and other parts of the O.sarsii range, were characterized by high haplotype diversity with a significant number of private haplotypes being mostly satellites to the two dominant haplotypes, each belonging to a different mtDNA clade. Demographic analyses indicated that the demographic and spatial expansion of O.sarsii in the Barents Sea most plausibly has started in the Bølling–Allerød interstadial during the deglaciation of the western margin of the Barents Sea.

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Polar cod in jeopardy under the retreating Arctic sea ice

Communications Biology ◽

10.1038/s42003-019-0649-2 ◽

2019 ◽

Vol 2 (1) ◽

Cited By ~ 6

Author(s):

Mats Brockstedt Olsen Huserbråten ◽

Elena Eriksen ◽

Harald Gjøsæter ◽

Frode Vikebø

Keyword(s):

Sea Ice ◽

Barents Sea ◽

Keystone Species ◽

Ice Cover ◽

Arctic Sea Ice ◽

Biophysical Model ◽

The Arctic ◽

Polar Cod ◽

Arctic Sea ◽

Shelf Sea

Abstract The Arctic amplification of global warming is causing the Arctic-Atlantic ice edge to retreat at unprecedented rates. Here we show how variability and change in sea ice cover in the Barents Sea, the largest shelf sea of the Arctic, affect the population dynamics of a keystone species of the ice-associated food web, the polar cod (Boreogadus saida). The data-driven biophysical model of polar cod early life stages assembled here predicts a strong mechanistic link between survival and variation in ice cover and temperature, suggesting imminent recruitment collapse should the observed ice-reduction and heating continue. Backtracking of drifting eggs and larvae from observations also demonstrates a northward retreat of one of two clearly defined spawning assemblages, possibly in response to warming. With annual to decadal ice-predictions under development the mechanistic physical-biological links presented here represent a powerful tool for making long-term predictions for the propagation of polar cod stocks.

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U–Pb geochronology of Cretaceous magmatism on Svalbard and Franz Josef Land, Barents Sea Large Igneous Province

Geological Magazine ◽

10.1017/s0016756813000162 ◽

2013 ◽

Vol 150 (6) ◽

pp. 1127-1135 ◽

Cited By ~ 76

Author(s):

FERNANDO CORFU ◽

STÉPHANE POLTEAU ◽

SVERRE PLANKE ◽

JAN INGE FALEIDE ◽

HENRIK SVENSEN ◽

...

Keyword(s):

Thermal Ionization Mass Spectrometry ◽

Barents Sea ◽

Large Igneous Province ◽

The Arctic ◽

Ionization Mass ◽

Franz Josef Land ◽

Igneous Province ◽

Stratigraphic Record ◽

Single Grain ◽

Cretaceous Magmatism

AbstractThe opening of the Arctic oceanic basins in the Mesozoic and Cenozoic proceeded in steps, with episodes of magmatism and sedimentation marking specific stages in this development. In addition to the stratigraphic record provided by sediments and fossils, the intrusive and extrusive rocks yield important information on this evolution. This study has determined the ages of mafic sills and a felsic tuff in Svalbard and Franz Josef Land using the isotope dilution thermal ionization mass spectrometry (ID-TIMS) U–Pb method on zircon, baddeleyite, titanite and rutile. The results indicate crystallization of the Diabasodden sill at 124.5 ± 0.2 Ma and the Linnévatn sill at 124.7 ± 0.3 Ma, the latter also containing slightly younger secondary titanite with an age of 123.9 ± 0.3 Ma. A bentonite in the Helvetiafjellet Formation, also on Svalbard, has an age of 123.3 ± 0.2 Ma. Zircon in mafic sills intersected by drill cores in Franz Josef Land indicate an age of 122.7 Ma for a thick sill on Severnaya Island and a single grain age of ≥122.2 ± 1.1 Ma for a thinner sill on Nagurskaya Island. These data emphasize the importance and relatively short-lived nature of the Cretaceous magmatic event in the region.

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Mass balance controls on sediment scour and bedrock erosion in waterfall plunge pools

Geology ◽

10.1130/g48881.1 ◽

2021 ◽

Author(s):

Joel S. Scheingross ◽

Michael P. Lamb

Keyword(s):

Sediment Transport ◽

Mass Balance ◽

River Discharge ◽

Sediment Load ◽

Sediment Flux ◽

Habitat Availability ◽

Flux Divergence ◽

Plunge Pool ◽

Bedrock Erosion ◽

Recurrence Intervals

Waterfall plunge pools experience cycles of sediment aggradation and scour that modulate bedrock erosion, habitat availability, and hazard potential. We calculate sediment flux divergence to evaluate the conditions under which pools deposit and scour sediment by comparing the sediment transport capacities of waterfall plunge pools (Qsc_pool) and their adjacent river reaches (Qsc_river). Results show that pools fill with sediment at low river discharge because the waterfall jet is not strong enough to transport the supplied sediment load out of the pool. As discharge increases, the waterfall jet strengthens, allowing pools to transport sediment at greater rates than in adjacent river reaches. This causes sediment scour from pools and bar building at the downstream pool boundary. While pools may be partially emptied of sediment at modest discharge, floods with recurrence intervals >10 yr are typically required for pools to scour to bedrock. These results allow new constraints on paleodischarge estimates made from sediment deposited in plunge pool bars and suggest that bedrock erosion at waterfalls with plunge pools occurs during larger floods than in river reaches lacking waterfalls.

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Arctic Freshwater in CMIP6: Declining Sea Ice, Increasing Ocean Storage and Export

10.5194/egusphere-egu21-6391 ◽

2021 ◽

Author(s):

Hannah Zanowski ◽

Alexandra Jahn ◽

Marika Holland

Keyword(s):

Sea Ice ◽

21St Century ◽

Barents Sea ◽

The Arctic ◽

Historical Period ◽

Freshwater Flux ◽

Bering Strait ◽

The Barents Sea ◽

Late 21St Century ◽

Freshwater Export

Recently, the Arctic has undergone substantial changes in sea ice cover and the hydrologic cycle, both of which strongly impact the freshwater storage in, and export from, the Arctic Ocean. Here we analyze Arctic freshwater storage and fluxes in 7 climate models from the Coupled Model Intercomparison Project phase 6 (CMIP6) and assess their agreement over the historical period (1980-2000) and in two future emissions scenarios, SSP1-2.6 and SSP5-8.5. In the historical simulation, few models agree closely with observations over 1980-2000. In both future scenarios the models show an increase in liquid (ocean) freshwater storage in conjunction with a reduction in solid storage and fluxes through the major Arctic gateways (Bering Strait, Fram Strait, Davis Strait, and the Barents Sea Opening) that is typically larger for SSP5-8.5 than SSP1-2.6. The liquid fluxes through the gateways exhibit a more complex pattern, with models exhibiting a change in sign of the freshwater flux through the Barents Sea Opening and little change in the flux through the Bering Strait in addition to increased export from the remaining straits by the end of the 21st century. A decomposition of the liquid fluxes into their salinity and volume contributions shows that the Barents Sea flux changes are driven by salinity changes, while the Bering Strait flux changes are driven by compensating salinity and volume changes. In the straits west of Greenland (Nares, Barrow, and Davis straits), the models disagree on whether there will be a decrease, increase, or steady liquid freshwater export in the early to mid 21st century, although they mostly show increased liquid freshwater export in the late 21st century. The underlying cause of this is a difference in the magnitude and timing of a simulated decrease in the volume flux through these straits. Although the models broadly agree on the sign of late 21st century storage and flux changes, substantial differences exist between the magnitude of these changes and the models&#8217; Arctic mean states, which shows no fundamental improvement in the models compared to CMIP5.

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