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...
Published in: | Earth and Space Science |
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Main Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
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AGU (American Geophysical Union)
2023
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Online Access: | https://oceanrep.geomar.de/id/eprint/59228/ https://oceanrep.geomar.de/id/eprint/59228/1/Singhroha%20et%20al.pdf https://oceanrep.geomar.de/id/eprint/59228/7/2023ea003068-sup-0001-supporting%20information%20si-s01.docx https://doi.org/10.1029/2023EA003068 |
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ftoceanrep:oai:oceanrep.geomar.de:59228 2024-02-11T10:09:02+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 Domel, Przemyslaw Dannowski, Anke Cooke, Frances Bünz, Stefan 2023-10-28 text https://oceanrep.geomar.de/id/eprint/59228/ https://oceanrep.geomar.de/id/eprint/59228/1/Singhroha%20et%20al.pdf https://oceanrep.geomar.de/id/eprint/59228/7/2023ea003068-sup-0001-supporting%20information%20si-s01.docx https://doi.org/10.1029/2023EA003068 en eng AGU (American Geophysical Union) Wiley https://oceanrep.geomar.de/id/eprint/59228/1/Singhroha%20et%20al.pdf https://oceanrep.geomar.de/id/eprint/59228/7/2023ea003068-sup-0001-supporting%20information%20si-s01.docx Singhroha, S., Schramm, B., Plaza‐Faverola, A., Domel, P., Dannowski, A. , Cooke, F. and Bünz, S. (2023) Stress Constraints From Shear-Wave Analysis in Shallow Sediments at an Actively Seeping Pockmark on the W-Svalbard Margin. Open Access Earth and Space Science, 10 (10). e2023EA003068. DOI 10.1029/2023EA003068 <https://doi.org/10.1029/2023EA003068>. doi:10.1029/2023EA003068 cc_by_4.0 info:eu-repo/semantics/openAccess Article PeerReviewed 2023 ftoceanrep https://doi.org/10.1029/2023EA003068 2024-01-15T00:27:49Z 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. Key Points The S-wave analysis using ocean-bottom seismic (OBS) data indicates seismic anisotropy around a seeping pockmark on the W-Svalbard Margin The occurrence and orientation of symmetry planes in shallow anisotropic sediments vary across the pockmark Combined analyses using S-wave and 3-D seismic data suggest that preferred fault and fracture ... Article in Journal/Newspaper Svalbard Svalbard margin Lunde OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Lunde ENVELOPE(50.467,50.467,-66.967,-66.967) Svalbard Earth and Space Science 10 10 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
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. Key Points The S-wave analysis using ocean-bottom seismic (OBS) data indicates seismic anisotropy around a seeping pockmark on the W-Svalbard Margin The occurrence and orientation of symmetry planes in shallow anisotropic sediments vary across the pockmark Combined analyses using S-wave and 3-D seismic data suggest that preferred fault and fracture ... |
format |
Article in Journal/Newspaper |
author |
Singhroha, Sunny Schramm, Bettina Plaza‐Faverola, Andreia Domel, Przemyslaw Dannowski, Anke Cooke, Frances Bünz, Stefan |
spellingShingle |
Singhroha, Sunny Schramm, Bettina Plaza‐Faverola, Andreia Domel, Przemyslaw Dannowski, Anke Cooke, Frances 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 Domel, Przemyslaw Dannowski, Anke Cooke, Frances 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 |
AGU (American Geophysical Union) |
publishDate |
2023 |
url |
https://oceanrep.geomar.de/id/eprint/59228/ https://oceanrep.geomar.de/id/eprint/59228/1/Singhroha%20et%20al.pdf https://oceanrep.geomar.de/id/eprint/59228/7/2023ea003068-sup-0001-supporting%20information%20si-s01.docx https://doi.org/10.1029/2023EA003068 |
long_lat |
ENVELOPE(50.467,50.467,-66.967,-66.967) |
geographic |
Lunde Svalbard |
geographic_facet |
Lunde Svalbard |
genre |
Svalbard Svalbard margin Lunde |
genre_facet |
Svalbard Svalbard margin Lunde |
op_relation |
https://oceanrep.geomar.de/id/eprint/59228/1/Singhroha%20et%20al.pdf https://oceanrep.geomar.de/id/eprint/59228/7/2023ea003068-sup-0001-supporting%20information%20si-s01.docx Singhroha, S., Schramm, B., Plaza‐Faverola, A., Domel, P., Dannowski, A. , Cooke, F. and Bünz, S. (2023) Stress Constraints From Shear-Wave Analysis in Shallow Sediments at an Actively Seeping Pockmark on the W-Svalbard Margin. Open Access Earth and Space Science, 10 (10). e2023EA003068. DOI 10.1029/2023EA003068 <https://doi.org/10.1029/2023EA003068>. doi:10.1029/2023EA003068 |
op_rights |
cc_by_4.0 info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1029/2023EA003068 |
container_title |
Earth and Space Science |
container_volume |
10 |
container_issue |
10 |
_version_ |
1790608737406287872 |