Fracture-controlled fluid transport supports microbial methane-oxidizing communities at Vestnesa Ridge
We report a rare observation of a mini-fracture in near-surface sediments (30 cm below the seafloor) visualized using a rotational scanning X-ray of a core recovered from the Lomvi pockmark, Vestnesa Ridge, west of Svalbard (1200 m water depth). Porewater geochemistry and lipid biomarker signatures...
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Language: | English |
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European Geosciences Union (EGU)
2019
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Online Access: | https://hdl.handle.net/10037/15839 https://doi.org/10.5194/bg-16-2221-2019 |
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ftunivtroemsoe:oai:munin.uit.no:10037/15839 2023-05-15T14:27:40+02:00 Fracture-controlled fluid transport supports microbial methane-oxidizing communities at Vestnesa Ridge Yao, Haoyi Hong, Wei-Li Panieri, Giuliana Sauer, Simone Torres, Marta E. Lehmann, Moritz F. Gründger, Friederike Niemann, Helge 2019-05-29 https://hdl.handle.net/10037/15839 https://doi.org/10.5194/bg-16-2221-2019 eng eng European Geosciences Union (EGU) Yao, H. (2020). Reconstruction of past and present methane emission in the Arctic cold seeps using biogeochemical proxies. (Doctoral thesis). https://hdl.handle.net/10037/17821. Biogeosciences Norges forskningsråd: 223259 Yao, H., Hong, H., Panieri, G., Sauer, S., Torres, M.E., Lehmann, M.F., Gründger, F., Niemann, H.(2019) Fracture-controlled fluid transport supports microbial methane-oxidizing communities at Vestnesa Ridge. Biogeosciences,16 (10), 2221-2232. http://dx.doi.org/10.5194/bg-16-2221-2019 FRIDAID 1701329 https://doi.org/10.5194/bg-16-2221-2019 1726-4170 1726-4189 https://hdl.handle.net/10037/15839 openAccess VDP::Technology: 500::Rock and petroleum disciplines: 510::Geological engineering: 513 VDP::Teknologi: 500::Berg‑ og petroleumsfag: 510::Geoteknikk: 513 Journal article Peer reviewed 2019 ftunivtroemsoe https://doi.org/10.5194/bg-16-2221-2019 2021-06-25T17:56:37Z We report a rare observation of a mini-fracture in near-surface sediments (30 cm below the seafloor) visualized using a rotational scanning X-ray of a core recovered from the Lomvi pockmark, Vestnesa Ridge, west of Svalbard (1200 m water depth). Porewater geochemistry and lipid biomarker signatures revealed clear differences in the geochemical and biogeochemical regimes of this core compared with two additional unfractured cores recovered from pockmark sites at Vestnesa Ridge, which we attribute to differential methane transport mechanisms. In the sediment core featuring the shallow mini-fracture at pockmark Lomvi, we observed high concentrations of both methane and sulfate throughout the core in tandem with moderately elevated values for total alkalinity, 13C-depleted dissolved inorganic carbon (DIC), and 13C-depleted lipid biomarkers (diagnostic for the slow-growing microbial communities mediating the anaerobic oxidation of methane with sulfate – AOM). In a separate unfractured core, recovered from the same pockmark about 80 m away from the fractured core, we observed complete sulfate depletion in the top centimeters of the sediment and much more pronounced signatures of AOM than in the fractured core. Our data indicate a gas advection-dominated transport mode in both cores, facilitating methane migration into sulfate-rich surface sediments. However, the moderate expression of AOM signals suggest a rather recent onset of gas migration at the site of the fractured core, while the geochemical evidence for a well-established AOM community at the second coring site suggest that gas migration has been going on for a longer period of time. A third core recovered from another pockmark along the Vestnesa Ridge Lunde pockmark was dominated by diffusive transport with only weak geochemical and biogeochemical evidence for AOM. Our study highlights that advective fluid and gas transport supported by mini-fractures can be important in modulating methane dynamics in surface sediments. Article in Journal/Newspaper Arctic Lomvi Svalbard Lunde University of Tromsø: Munin Open Research Archive Lunde ENVELOPE(50.467,50.467,-66.967,-66.967) Svalbard Biogeosciences 16 10 2221 2232 |
institution |
Open Polar |
collection |
University of Tromsø: Munin Open Research Archive |
op_collection_id |
ftunivtroemsoe |
language |
English |
topic |
VDP::Technology: 500::Rock and petroleum disciplines: 510::Geological engineering: 513 VDP::Teknologi: 500::Berg‑ og petroleumsfag: 510::Geoteknikk: 513 |
spellingShingle |
VDP::Technology: 500::Rock and petroleum disciplines: 510::Geological engineering: 513 VDP::Teknologi: 500::Berg‑ og petroleumsfag: 510::Geoteknikk: 513 Yao, Haoyi Hong, Wei-Li Panieri, Giuliana Sauer, Simone Torres, Marta E. Lehmann, Moritz F. Gründger, Friederike Niemann, Helge Fracture-controlled fluid transport supports microbial methane-oxidizing communities at Vestnesa Ridge |
topic_facet |
VDP::Technology: 500::Rock and petroleum disciplines: 510::Geological engineering: 513 VDP::Teknologi: 500::Berg‑ og petroleumsfag: 510::Geoteknikk: 513 |
description |
We report a rare observation of a mini-fracture in near-surface sediments (30 cm below the seafloor) visualized using a rotational scanning X-ray of a core recovered from the Lomvi pockmark, Vestnesa Ridge, west of Svalbard (1200 m water depth). Porewater geochemistry and lipid biomarker signatures revealed clear differences in the geochemical and biogeochemical regimes of this core compared with two additional unfractured cores recovered from pockmark sites at Vestnesa Ridge, which we attribute to differential methane transport mechanisms. In the sediment core featuring the shallow mini-fracture at pockmark Lomvi, we observed high concentrations of both methane and sulfate throughout the core in tandem with moderately elevated values for total alkalinity, 13C-depleted dissolved inorganic carbon (DIC), and 13C-depleted lipid biomarkers (diagnostic for the slow-growing microbial communities mediating the anaerobic oxidation of methane with sulfate – AOM). In a separate unfractured core, recovered from the same pockmark about 80 m away from the fractured core, we observed complete sulfate depletion in the top centimeters of the sediment and much more pronounced signatures of AOM than in the fractured core. Our data indicate a gas advection-dominated transport mode in both cores, facilitating methane migration into sulfate-rich surface sediments. However, the moderate expression of AOM signals suggest a rather recent onset of gas migration at the site of the fractured core, while the geochemical evidence for a well-established AOM community at the second coring site suggest that gas migration has been going on for a longer period of time. A third core recovered from another pockmark along the Vestnesa Ridge Lunde pockmark was dominated by diffusive transport with only weak geochemical and biogeochemical evidence for AOM. Our study highlights that advective fluid and gas transport supported by mini-fractures can be important in modulating methane dynamics in surface sediments. |
format |
Article in Journal/Newspaper |
author |
Yao, Haoyi Hong, Wei-Li Panieri, Giuliana Sauer, Simone Torres, Marta E. Lehmann, Moritz F. Gründger, Friederike Niemann, Helge |
author_facet |
Yao, Haoyi Hong, Wei-Li Panieri, Giuliana Sauer, Simone Torres, Marta E. Lehmann, Moritz F. Gründger, Friederike Niemann, Helge |
author_sort |
Yao, Haoyi |
title |
Fracture-controlled fluid transport supports microbial methane-oxidizing communities at Vestnesa Ridge |
title_short |
Fracture-controlled fluid transport supports microbial methane-oxidizing communities at Vestnesa Ridge |
title_full |
Fracture-controlled fluid transport supports microbial methane-oxidizing communities at Vestnesa Ridge |
title_fullStr |
Fracture-controlled fluid transport supports microbial methane-oxidizing communities at Vestnesa Ridge |
title_full_unstemmed |
Fracture-controlled fluid transport supports microbial methane-oxidizing communities at Vestnesa Ridge |
title_sort |
fracture-controlled fluid transport supports microbial methane-oxidizing communities at vestnesa ridge |
publisher |
European Geosciences Union (EGU) |
publishDate |
2019 |
url |
https://hdl.handle.net/10037/15839 https://doi.org/10.5194/bg-16-2221-2019 |
long_lat |
ENVELOPE(50.467,50.467,-66.967,-66.967) |
geographic |
Lunde Svalbard |
geographic_facet |
Lunde Svalbard |
genre |
Arctic Lomvi Svalbard Lunde |
genre_facet |
Arctic Lomvi Svalbard Lunde |
op_relation |
Yao, H. (2020). Reconstruction of past and present methane emission in the Arctic cold seeps using biogeochemical proxies. (Doctoral thesis). https://hdl.handle.net/10037/17821. Biogeosciences Norges forskningsråd: 223259 Yao, H., Hong, H., Panieri, G., Sauer, S., Torres, M.E., Lehmann, M.F., Gründger, F., Niemann, H.(2019) Fracture-controlled fluid transport supports microbial methane-oxidizing communities at Vestnesa Ridge. Biogeosciences,16 (10), 2221-2232. http://dx.doi.org/10.5194/bg-16-2221-2019 FRIDAID 1701329 https://doi.org/10.5194/bg-16-2221-2019 1726-4170 1726-4189 https://hdl.handle.net/10037/15839 |
op_rights |
openAccess |
op_doi |
https://doi.org/10.5194/bg-16-2221-2019 |
container_title |
Biogeosciences |
container_volume |
16 |
container_issue |
10 |
container_start_page |
2221 |
op_container_end_page |
2232 |
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1766301506671214592 |