Stress Constraints From Shear-Wave Analysis in Shallow Sediments at an Actively Seeping Pockmark on the W-Svalbard Margin
Mechanisms related to sub-seabed fluid flow processes are complex and inadequately understood. Petrophysical properties, availability of gases, topography, stress directions, and various geological parameters determine the location and intensity of leakage which change over time. From tens of seaflo...
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Online Access: | https://hdl.handle.net/10037/31441 https://doi.org/10.1029/2023EA003068 |
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ftunivtroemsoe:oai:munin.uit.no:10037/31441 2023-11-05T03:45:18+01:00 Stress Constraints From Shear-Wave Analysis in Shallow Sediments at an Actively Seeping Pockmark on the W-Svalbard Margin Singhroha, Sunny Schramm, Bettina Plaza Faverola, Andreia Aletia Domel, Przemyslaw Dannowski, Anke Cooke, Frances Ann Bünz, Stefan 2023-09-28 https://hdl.handle.net/10037/31441 https://doi.org/10.1029/2023EA003068 eng eng Wiley Earth and Space Science Singhroha S, Schramm B, Plaza Faverola A, Domel P, Dannowski A, Cooke FA, Bünz S. Stress Constraints From Shear-Wave Analysis in Shallow Sediments at an Actively Seeping Pockmark on the W-Svalbard Margin. Earth and Space Science. 2023;10(10) FRIDAID 2181591 doi:10.1029/2023EA003068 2333-5084 https://hdl.handle.net/10037/31441 Attribution 4.0 International (CC BY 4.0) openAccess Copyright 2023 The Author(s) https://creativecommons.org/licenses/by/4.0 Journal article Tidsskriftartikkel Peer reviewed publishedVersion 2023 ftunivtroemsoe https://doi.org/10.1029/2023EA003068 2023-10-11T23:07:51Z Mechanisms related to sub-seabed fluid flow processes are complex and inadequately understood. Petrophysical properties, availability of gases, topography, stress directions, and various geological parameters determine the location and intensity of leakage which change over time. From tens of seafloor pockmarks mapped along Vestnesa Ridge on the west-Svalbard margin, only six show persistent present-day seepage activity in sonar data. To investigate the causes of such restricted gas seepage, we conducted a study of anisotropy within the conduit feeding one of these active pockmarks (i.e., Lunde Pockmark). Lunde is ∼400–500 m in diameter, and atop a ∼300–400 m wide seismic chimney structure. We study seismic anisotropy using converted S-wave data from 22 ocean-bottom seismometers (OBSs) located in and around the pockmark. We investigate differences in symmetry plane directions in anisotropic media using null energy symmetries in transverse components. Subsurface stress distribution affects fault/fracture orientations and seismic anisotropy, and we use S-wave and high-resolution 3D seismic data to infer stress regimes in and around the active seep site and study the effect of stresses on seepage. We observe the occurrence of changes in dominant fault/fracture and horizontal stress orientations in and around Lunde Pockmark and conclude minimum (NE-SW) and maximum (SE-NW) horizontal stress directions. Our analysis indicates a potential correlation between hydrofractures and horizontal stresses, with up to a ∼32% higher probability of alignment of hydrofractures and faults perpendicular to the inferred minimum horizontal stress direction beneath the Lunde Pockmark area. Article in Journal/Newspaper Svalbard Svalbard margin Lunde University of Tromsø: Munin Open Research Archive Earth and Space Science 10 10 |
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Open Polar |
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University of Tromsø: Munin Open Research Archive |
op_collection_id |
ftunivtroemsoe |
language |
English |
description |
Mechanisms related to sub-seabed fluid flow processes are complex and inadequately understood. Petrophysical properties, availability of gases, topography, stress directions, and various geological parameters determine the location and intensity of leakage which change over time. From tens of seafloor pockmarks mapped along Vestnesa Ridge on the west-Svalbard margin, only six show persistent present-day seepage activity in sonar data. To investigate the causes of such restricted gas seepage, we conducted a study of anisotropy within the conduit feeding one of these active pockmarks (i.e., Lunde Pockmark). Lunde is ∼400–500 m in diameter, and atop a ∼300–400 m wide seismic chimney structure. We study seismic anisotropy using converted S-wave data from 22 ocean-bottom seismometers (OBSs) located in and around the pockmark. We investigate differences in symmetry plane directions in anisotropic media using null energy symmetries in transverse components. Subsurface stress distribution affects fault/fracture orientations and seismic anisotropy, and we use S-wave and high-resolution 3D seismic data to infer stress regimes in and around the active seep site and study the effect of stresses on seepage. We observe the occurrence of changes in dominant fault/fracture and horizontal stress orientations in and around Lunde Pockmark and conclude minimum (NE-SW) and maximum (SE-NW) horizontal stress directions. Our analysis indicates a potential correlation between hydrofractures and horizontal stresses, with up to a ∼32% higher probability of alignment of hydrofractures and faults perpendicular to the inferred minimum horizontal stress direction beneath the Lunde Pockmark area. |
format |
Article in Journal/Newspaper |
author |
Singhroha, Sunny Schramm, Bettina Plaza Faverola, Andreia Aletia Domel, Przemyslaw Dannowski, Anke Cooke, Frances Ann Bünz, Stefan |
spellingShingle |
Singhroha, Sunny Schramm, Bettina Plaza Faverola, Andreia Aletia Domel, Przemyslaw Dannowski, Anke Cooke, Frances Ann Bünz, Stefan Stress Constraints From Shear-Wave Analysis in Shallow Sediments at an Actively Seeping Pockmark on the W-Svalbard Margin |
author_facet |
Singhroha, Sunny Schramm, Bettina Plaza Faverola, Andreia Aletia Domel, Przemyslaw Dannowski, Anke Cooke, Frances Ann Bünz, Stefan |
author_sort |
Singhroha, Sunny |
title |
Stress Constraints From Shear-Wave Analysis in Shallow Sediments at an Actively Seeping Pockmark on the W-Svalbard Margin |
title_short |
Stress Constraints From Shear-Wave Analysis in Shallow Sediments at an Actively Seeping Pockmark on the W-Svalbard Margin |
title_full |
Stress Constraints From Shear-Wave Analysis in Shallow Sediments at an Actively Seeping Pockmark on the W-Svalbard Margin |
title_fullStr |
Stress Constraints From Shear-Wave Analysis in Shallow Sediments at an Actively Seeping Pockmark on the W-Svalbard Margin |
title_full_unstemmed |
Stress Constraints From Shear-Wave Analysis in Shallow Sediments at an Actively Seeping Pockmark on the W-Svalbard Margin |
title_sort |
stress constraints from shear-wave analysis in shallow sediments at an actively seeping pockmark on the w-svalbard margin |
publisher |
Wiley |
publishDate |
2023 |
url |
https://hdl.handle.net/10037/31441 https://doi.org/10.1029/2023EA003068 |
genre |
Svalbard Svalbard margin Lunde |
genre_facet |
Svalbard Svalbard margin Lunde |
op_relation |
Earth and Space Science Singhroha S, Schramm B, Plaza Faverola A, Domel P, Dannowski A, Cooke FA, Bünz S. Stress Constraints From Shear-Wave Analysis in Shallow Sediments at an Actively Seeping Pockmark on the W-Svalbard Margin. Earth and Space Science. 2023;10(10) FRIDAID 2181591 doi:10.1029/2023EA003068 2333-5084 https://hdl.handle.net/10037/31441 |
op_rights |
Attribution 4.0 International (CC BY 4.0) openAccess Copyright 2023 The Author(s) https://creativecommons.org/licenses/by/4.0 |
op_doi |
https://doi.org/10.1029/2023EA003068 |
container_title |
Earth and Space Science |
container_volume |
10 |
container_issue |
10 |
_version_ |
1781707207936573440 |