scholarly journals Geological Controls on Fluid Flow and Gas Hydrate Pingo Development on the Barents Sea Margin

2019 ◽  
Vol 20 (2) ◽  
pp. 630-650 ◽  
Author(s):  
M. Waage ◽  
A. Portnov ◽  
P. Serov ◽  
S. Bünz ◽  
K. A. Waghorn ◽  
...  
2015 ◽  
Vol 66 ◽  
pp. 861-872 ◽  
Author(s):  
Sunil Vadakkepuliyambatta ◽  
Matthew J. Hornbach ◽  
Stefan Bünz ◽  
Benjamin J. Phrampus

2020 ◽  
Author(s):  
Pavel Serov ◽  
Henry Patton ◽  
Malin Waage ◽  
Calvin Shackleton ◽  
Jurgen Mienert ◽  
...  

<p>During the past ~2.6 Ma, some 30 glaciations have caused episodic high pressure and low temperature conditions and forced growth and decay of extensive subglacial methane hydrate accumulations globally. Research on Arctic methane release has primarily focused on warm, interglacial episodes when hydrates became unstable across territories either abandoned by former ice sheets or affected by permafrost degradation. Here we present a new mechanism – the subglacial erosion of gas hydrate-bearing sediments – that actively mobilizes methane in hydrate and dissolved form and delivers it to the ice sheet margin. We investigate this mechanism using geophysical imaging and ice sheet/gas hydrate modeling focused on a study site in Storfjordrenna, that hosted large ice stream draining the Barents Sea ice sheet. During the last glacial, we find that this ice stream overrode an extensive cluster of conduits that supplied a continuous methane flux from a deep, thermogenic source and delivered it to the subglacial environment. Our analysis reveals that 15,000 to 44,000 m<sup>3</sup> of gas hydrates were subglacially eroded from the 17 km<sup>2</sup> study site and transported to the shelf-edge. Given the abundance of natural gas reservoirs across the Barents Sea and marine-based glaciated petroleum provinces elsewhere, we propose that this mechanism had the potential to mobilize a substantial flux of subglacial methane throughout multiple Quaternary glacial episodes.</p>


2012 ◽  
Vol 331-332 ◽  
pp. 305-314 ◽  
Author(s):  
S. Chand ◽  
T. Thorsnes ◽  
L. Rise ◽  
H. Brunstad ◽  
D. Stoddart ◽  
...  

2021 ◽  
Author(s):  
Claudio Argentino ◽  
Kate Waghorn ◽  
Sunil Vadakkepuliyambatta ◽  
Stéphane Polteau ◽  
Stefan Bünz ◽  
...  

<p>Methane emissions from Arctic continental margins may increase due to global warming. Present-day ocean fluxes seem to provide a minor contribution to the atmosphere methane pool, but large uncertainties still remain on the magnitude of future emissions from methane seeps and gas hydrate-bearing sediments. The Barents Sea is a natural laboratory to study the evolution of methane seeps in relation to climate change, as it recorded several phases of ice-sheet advance and retreat during the Pleistocene. Glaciations and its concurrent denudation of the Barents Sea influenced the subsurface, causing reservoir expansion and fracturing, thereby driving hydrocarbon (mostly gas) migration which resulted in a sustained regional fluid flow system. New data from this area can shed light on future response of other high-latitude continental shelves worldwide. Here, we present reconstructed methane emission dynamics at Leirdjupet Fault Complex (LFC), SW Barents Sea, since last deglaciation (occurred after ~19 cal Ka BP). The geochemical composition of sediment cores indicate prolonged methane emissions, which started after 14.5 cal Ka BP. Geochemical proxies for anaerobic oxidation of methane in the sediment (barium, calcium and sulfur enrichments, isotopic composition of foraminifera) indicate an overall decrease in seepage intensity over the Holocene toward present-day conditions. Methane-derived authigenic carbonates with aragonite mineralogy and heavy δ<sup>18</sup>O signature recorded an episode of gas hydrate destabilization in this region. Paleo-hydrate stability models suggest that this event was triggered by the influx of warm Atlantic water and isostatic uplift linked to the retreat of the Barents Sea Ice Sheet. Present-day distribution of methane seeps at LFC is strongly linked to underlying faults. Methane hydrates are stable in the southern part of the investigated seepage area and might respond to a future increase in bottom water temperatures.</p>


2016 ◽  
Vol 97 ◽  
pp. 302-309 ◽  
Author(s):  
Peter Klitzke ◽  
Manja Luzi-Helbing ◽  
Judith M. Schicks ◽  
Mauro Cacace ◽  
Antoine B. Jacquey ◽  
...  

1998 ◽  
Vol 18 (1) ◽  
pp. 26-33 ◽  
Author(s):  
J. S. Laberg ◽  
K. Andreassen ◽  
S.-M. Knutsen

Author(s):  
Valeriy G. Yakubenko ◽  
Anna L. Chultsova

Identification of water masses in areas with complex water dynamics is a complex task, which is usually solved by the method of expert assessments. In this paper, it is proposed to use a formal procedure based on the application of the method of optimal multiparametric analysis (OMP analysis). The data of field measurements obtained in the 68th cruise of the R/V “Academician Mstislav Keldysh” in the summer of 2017 in the Barents Sea on the distribution of temperature, salinity, oxygen, silicates, nitrogen, and phosphorus concentration are used as a data for research. A comparison of the results with data on the distribution of water masses in literature based on expert assessments (Oziel et al., 2017), allows us to conclude about their close structural similarity. Some differences are related to spatial and temporal shifts of measurements. This indicates the feasibility of using the OMP analysis technique in oceanological studies to obtain quantitative data on the spatial distribution of different water masses.


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