Crustal and uppermost mantle structure of the Porcupine Basin west of Ireland from seismic and gravity methods
International audience The Porcupine basin is a failed rift that formed during the opening of the North Atlantic Ocean. Here, we provide additional insights into the crustal structure of the northern Porcupine Basin and assess the degree of crustal extension from long streamer seismic data and free-...
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ftunivparis:oai:HAL:hal-03666846v1 2023-05-15T17:35:29+02:00 Crustal and uppermost mantle structure of the Porcupine Basin west of Ireland from seismic and gravity methods Tomar, Gaurav O'Reilly, Brian Prada, Manel Hardy, Robert Bean, Christopher Singh, Satish Bérdi, Laura Institut de Physique du Globe de Paris (IPGP (UMR_7154)) Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité) This project was funded by the Irish centre for Research in Applied Geosciences (iCRAG), Science Foundation Ireland (SFI), Irish Shelf and Petroleum Studies Group (ISPSG) of the Petroleum Infrastructure Programme (PiP) and DIAS. 2022-06 https://hal-univ-paris.archives-ouvertes.fr/hal-03666846 https://doi.org/10.1016/j.marpetgeo.2022.105652 en eng HAL CCSD Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.marpetgeo.2022.105652 hal-03666846 https://hal-univ-paris.archives-ouvertes.fr/hal-03666846 doi:10.1016/j.marpetgeo.2022.105652 ISSN: 0264-8172 Marine and Petroleum Geology https://hal-univ-paris.archives-ouvertes.fr/hal-03666846 Marine and Petroleum Geology, 2022, 140, pp.105652. ⟨10.1016/j.marpetgeo.2022.105652⟩ Mantle Serpentinisation Porcupine Basin Gravity Modelling Seismic Processing Mantle exhumation [SDE]Environmental Sciences info:eu-repo/semantics/article Journal articles 2022 ftunivparis https://doi.org/10.1016/j.marpetgeo.2022.105652 2023-03-15T17:38:31Z International audience The Porcupine basin is a failed rift that formed during the opening of the North Atlantic Ocean. Here, we provide additional insights into the crustal structure of the northern Porcupine Basin and assess the degree of crustal extension from long streamer seismic data and free-air gravity modelling. Recent re-processing of the 2013/2014 streamer data involved de-multiple and de-noise processing with pre-stack-depth migration using velocity models derived from reflection travel time tomography and full waveform inversion. Forward modelling of satellite gravity data was used to constrain the velocity and mass density of the basement and lower crust, where the seismic constraints are limited. Prior knowledge, from previous geophysical and geological studies, was included to guide the modelling and reconcile the gravity data with the seismic sections. It also served to minimize the non-uniqueness inherent in the forward problem. Crustal thinning occurs across the basin axis and increases southwards. We infer maximum stretching factor (β) at the basin axis, increasing from ∼4 to 6 in the North Porcupine at 52.5°N to >10 at ∼51°N in the Central Porcupine. The gravity modelling supports the presence of mantle serpentinisation, and the high β implies that crustal break up and mantle exhumation may have locally occurred in the Central Porcupine Basin, in agreement with previous seismic tomographic studies. Basaltic melt generation in the centre of the basin where the maximum bulk stretching factor exceeds10 in the hyper-extended crust may have led to localized sea-floor-spreading. Article in Journal/Newspaper North Atlantic Université de Paris: Portail HAL Marine and Petroleum Geology 140 105652 |
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Open Polar |
collection |
Université de Paris: Portail HAL |
op_collection_id |
ftunivparis |
language |
English |
topic |
Mantle Serpentinisation Porcupine Basin Gravity Modelling Seismic Processing Mantle exhumation [SDE]Environmental Sciences |
spellingShingle |
Mantle Serpentinisation Porcupine Basin Gravity Modelling Seismic Processing Mantle exhumation [SDE]Environmental Sciences Tomar, Gaurav O'Reilly, Brian Prada, Manel Hardy, Robert Bean, Christopher Singh, Satish Bérdi, Laura Crustal and uppermost mantle structure of the Porcupine Basin west of Ireland from seismic and gravity methods |
topic_facet |
Mantle Serpentinisation Porcupine Basin Gravity Modelling Seismic Processing Mantle exhumation [SDE]Environmental Sciences |
description |
International audience The Porcupine basin is a failed rift that formed during the opening of the North Atlantic Ocean. Here, we provide additional insights into the crustal structure of the northern Porcupine Basin and assess the degree of crustal extension from long streamer seismic data and free-air gravity modelling. Recent re-processing of the 2013/2014 streamer data involved de-multiple and de-noise processing with pre-stack-depth migration using velocity models derived from reflection travel time tomography and full waveform inversion. Forward modelling of satellite gravity data was used to constrain the velocity and mass density of the basement and lower crust, where the seismic constraints are limited. Prior knowledge, from previous geophysical and geological studies, was included to guide the modelling and reconcile the gravity data with the seismic sections. It also served to minimize the non-uniqueness inherent in the forward problem. Crustal thinning occurs across the basin axis and increases southwards. We infer maximum stretching factor (β) at the basin axis, increasing from ∼4 to 6 in the North Porcupine at 52.5°N to >10 at ∼51°N in the Central Porcupine. The gravity modelling supports the presence of mantle serpentinisation, and the high β implies that crustal break up and mantle exhumation may have locally occurred in the Central Porcupine Basin, in agreement with previous seismic tomographic studies. Basaltic melt generation in the centre of the basin where the maximum bulk stretching factor exceeds10 in the hyper-extended crust may have led to localized sea-floor-spreading. |
author2 |
Institut de Physique du Globe de Paris (IPGP (UMR_7154)) Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité) This project was funded by the Irish centre for Research in Applied Geosciences (iCRAG), Science Foundation Ireland (SFI), Irish Shelf and Petroleum Studies Group (ISPSG) of the Petroleum Infrastructure Programme (PiP) and DIAS. |
format |
Article in Journal/Newspaper |
author |
Tomar, Gaurav O'Reilly, Brian Prada, Manel Hardy, Robert Bean, Christopher Singh, Satish Bérdi, Laura |
author_facet |
Tomar, Gaurav O'Reilly, Brian Prada, Manel Hardy, Robert Bean, Christopher Singh, Satish Bérdi, Laura |
author_sort |
Tomar, Gaurav |
title |
Crustal and uppermost mantle structure of the Porcupine Basin west of Ireland from seismic and gravity methods |
title_short |
Crustal and uppermost mantle structure of the Porcupine Basin west of Ireland from seismic and gravity methods |
title_full |
Crustal and uppermost mantle structure of the Porcupine Basin west of Ireland from seismic and gravity methods |
title_fullStr |
Crustal and uppermost mantle structure of the Porcupine Basin west of Ireland from seismic and gravity methods |
title_full_unstemmed |
Crustal and uppermost mantle structure of the Porcupine Basin west of Ireland from seismic and gravity methods |
title_sort |
crustal and uppermost mantle structure of the porcupine basin west of ireland from seismic and gravity methods |
publisher |
HAL CCSD |
publishDate |
2022 |
url |
https://hal-univ-paris.archives-ouvertes.fr/hal-03666846 https://doi.org/10.1016/j.marpetgeo.2022.105652 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
ISSN: 0264-8172 Marine and Petroleum Geology https://hal-univ-paris.archives-ouvertes.fr/hal-03666846 Marine and Petroleum Geology, 2022, 140, pp.105652. ⟨10.1016/j.marpetgeo.2022.105652⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.marpetgeo.2022.105652 hal-03666846 https://hal-univ-paris.archives-ouvertes.fr/hal-03666846 doi:10.1016/j.marpetgeo.2022.105652 |
op_doi |
https://doi.org/10.1016/j.marpetgeo.2022.105652 |
container_title |
Marine and Petroleum Geology |
container_volume |
140 |
container_start_page |
105652 |
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1766134651027456000 |