Seismic and electrical geophysical characterization of an incipient coastal open-system pingo: Lagoon Pingo, Svalbard
Whilst there has been a recent appreciation for the role of open-system pingos in providing a fluid-flow conduit through continuous permafrost that enables methane release, the formation and internal structure of these ubiquitous permafrost-diagnostic landforms remains unclear. Here, we combine acti...
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Online Access: | https://hdl.handle.net/10037/24353 https://doi.org/10.1029/2021EA002093 |
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ftunivtroemsoe:oai:munin.uit.no:10037/24353 2023-05-15T13:05:44+02:00 Seismic and electrical geophysical characterization of an incipient coastal open-system pingo: Lagoon Pingo, Svalbard Hammock, Craig Paul Kulessa, Bernd Hiemstra, John F. Hodson, Andrew Hubbard, Alun 2021-12-24 https://hdl.handle.net/10037/24353 https://doi.org/10.1029/2021EA002093 eng eng Wiley Earth and Space Science Hammock, Kulessa B, Hiemstra, Hodson A, Hubbard AL. Seismic and electrical geophysical characterization of an incipient coastal open-system pingo: Lagoon Pingo, Svalbard. Earth and Space Science. 2021:1-32 FRIDAID 1975133 doi:10.1029/2021EA002093 2333-5084 https://hdl.handle.net/10037/24353 openAccess Copyright 2021 The Author(s) Journal article Tidsskriftartikkel Peer reviewed publishedVersion 2021 ftunivtroemsoe https://doi.org/10.1029/2021EA002093 2022-03-09T23:57:52Z Whilst there has been a recent appreciation for the role of open-system pingos in providing a fluid-flow conduit through continuous permafrost that enables methane release, the formation and internal structure of these ubiquitous permafrost-diagnostic landforms remains unclear. Here, we combine active-source seismic measurements with electrical resistivity tomography (ERT) to investigate the structural and subsurface characteristics of an incipient open-system pingo actively emitting methane within the glacio-isostatically uplifting fjord valley of Adventdalen, Svalbard. Wavefront inversion of seismic refractions delineate a spatially heterogenoeus active layer, whilst deeper reflections identify the lithological boundaries between marine sediments and underlying shales at ∼68 m depth (p-wave velocity of ∼1790 ms-1). Low geometric mean inverted resistivities of 40 – 150 Ωm highlight the dominance of saline permafrost, whilst elevated resistivities (∼2 kΩm) occur close to the groundwater spring and in heaved areas around the pingo. Based on our results, we speculate that segregation ice dominates the pingo structure, given the absence of a notable resistivity contrast characteristic of injection ice that is typically expected within early open-system pingo formation, and provides the most plausible geomorphic agent within the local fine-grained sedimentology. Our results thereby indicate that sediment grain size and moisture availability can provide important controls on pingo formation. This study shows that open-system pingos in coastal, saline permafrost environments may form differently, with implications for localized permafrost structure, its permeability to underlying gas reservoirs and consequent methane release. Article in Journal/Newspaper Adventdalen Ice open system Pingo permafrost Svalbard University of Tromsø: Munin Open Research Archive Adventdalen ENVELOPE(16.264,16.264,78.181,78.181) Svalbard Earth and Space Science 9 3 |
institution |
Open Polar |
collection |
University of Tromsø: Munin Open Research Archive |
op_collection_id |
ftunivtroemsoe |
language |
English |
description |
Whilst there has been a recent appreciation for the role of open-system pingos in providing a fluid-flow conduit through continuous permafrost that enables methane release, the formation and internal structure of these ubiquitous permafrost-diagnostic landforms remains unclear. Here, we combine active-source seismic measurements with electrical resistivity tomography (ERT) to investigate the structural and subsurface characteristics of an incipient open-system pingo actively emitting methane within the glacio-isostatically uplifting fjord valley of Adventdalen, Svalbard. Wavefront inversion of seismic refractions delineate a spatially heterogenoeus active layer, whilst deeper reflections identify the lithological boundaries between marine sediments and underlying shales at ∼68 m depth (p-wave velocity of ∼1790 ms-1). Low geometric mean inverted resistivities of 40 – 150 Ωm highlight the dominance of saline permafrost, whilst elevated resistivities (∼2 kΩm) occur close to the groundwater spring and in heaved areas around the pingo. Based on our results, we speculate that segregation ice dominates the pingo structure, given the absence of a notable resistivity contrast characteristic of injection ice that is typically expected within early open-system pingo formation, and provides the most plausible geomorphic agent within the local fine-grained sedimentology. Our results thereby indicate that sediment grain size and moisture availability can provide important controls on pingo formation. This study shows that open-system pingos in coastal, saline permafrost environments may form differently, with implications for localized permafrost structure, its permeability to underlying gas reservoirs and consequent methane release. |
format |
Article in Journal/Newspaper |
author |
Hammock, Craig Paul Kulessa, Bernd Hiemstra, John F. Hodson, Andrew Hubbard, Alun |
spellingShingle |
Hammock, Craig Paul Kulessa, Bernd Hiemstra, John F. Hodson, Andrew Hubbard, Alun Seismic and electrical geophysical characterization of an incipient coastal open-system pingo: Lagoon Pingo, Svalbard |
author_facet |
Hammock, Craig Paul Kulessa, Bernd Hiemstra, John F. Hodson, Andrew Hubbard, Alun |
author_sort |
Hammock, Craig Paul |
title |
Seismic and electrical geophysical characterization of an incipient coastal open-system pingo: Lagoon Pingo, Svalbard |
title_short |
Seismic and electrical geophysical characterization of an incipient coastal open-system pingo: Lagoon Pingo, Svalbard |
title_full |
Seismic and electrical geophysical characterization of an incipient coastal open-system pingo: Lagoon Pingo, Svalbard |
title_fullStr |
Seismic and electrical geophysical characterization of an incipient coastal open-system pingo: Lagoon Pingo, Svalbard |
title_full_unstemmed |
Seismic and electrical geophysical characterization of an incipient coastal open-system pingo: Lagoon Pingo, Svalbard |
title_sort |
seismic and electrical geophysical characterization of an incipient coastal open-system pingo: lagoon pingo, svalbard |
publisher |
Wiley |
publishDate |
2021 |
url |
https://hdl.handle.net/10037/24353 https://doi.org/10.1029/2021EA002093 |
long_lat |
ENVELOPE(16.264,16.264,78.181,78.181) |
geographic |
Adventdalen Svalbard |
geographic_facet |
Adventdalen Svalbard |
genre |
Adventdalen Ice open system Pingo permafrost Svalbard |
genre_facet |
Adventdalen Ice open system Pingo permafrost Svalbard |
op_relation |
Earth and Space Science Hammock, Kulessa B, Hiemstra, Hodson A, Hubbard AL. Seismic and electrical geophysical characterization of an incipient coastal open-system pingo: Lagoon Pingo, Svalbard. Earth and Space Science. 2021:1-32 FRIDAID 1975133 doi:10.1029/2021EA002093 2333-5084 https://hdl.handle.net/10037/24353 |
op_rights |
openAccess Copyright 2021 The Author(s) |
op_doi |
https://doi.org/10.1029/2021EA002093 |
container_title |
Earth and Space Science |
container_volume |
9 |
container_issue |
3 |
_version_ |
1766392180337803264 |