Imaging the crust and uppermost mantle structure of Portugal (West Iberia) with seismic ambient noise
Autor(a) principal: | |
---|---|
Data de Publicação: | 2022 |
Outros Autores: | , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10400.21/16104 |
Resumo: | We present a new high-resolution three-dimensional (3D) shear wave velocity (Vs) model of the crust and uppermost mantle beneath Portugal, inferred from ambient seismic noise tomography. We use broadband seismic data from a dense temporary deployment covering the entire Portuguese mainland between 2010 and 2012 in the scope of the WILAS project. Vertical component data are processed using phase correlation and phase weighted stack to obtain Empirical Green functions (EGF) for 3900 station pairs. Further, we use a random sampling and subset stacking strategy to measure robust Rayleigh wave group velocities in the period range 7-30 s and associated uncertainties. The tomographic inversion is performed in 2 steps: First, we determine group velocity lateral variations for each period. Next, we invert them at each grid point using a new trans-dimensional inversion scheme to obtain the 3D shear wave velocity model. The final 3D model extends from the upper crust (5 km) down to the uppermost mantle (60 km) and has a lateral resolution of similar to 50 km. In the upper and middle crust, the Vs anomaly pattern matches the tectonic units of the variscan massif and alpine basins. The transition between the Lusitanian Basin and the Ossa Morena Zone is marked by a contrast between moderate and high velocity anomalies, in addition to two arched earthquake lineations. Some faults, namely the Manteigas-Vilarica-Braganca fault and the Porto-Tomar-Ferreira do Alentejo fault, have a clear signature from the upper crust down to the uppermost mantle (60 km). Our 3D shear wave velocity model offers new insights into the continuation of the main tectonic units at depth and contributes to better understanding the seismicity of Portugal. |
id |
RCAP_1b3f9304c377d8bbfd9862e3ccbdb13c |
---|---|
oai_identifier_str |
oai:repositorio.ipl.pt:10400.21/16104 |
network_acronym_str |
RCAP |
network_name_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository_id_str |
7160 |
spelling |
Imaging the crust and uppermost mantle structure of Portugal (West Iberia) with seismic ambient noiseSeismic interferometrySurface waves and free oscillationsSeismic tomographyCrustal imagingCrustal structureWe present a new high-resolution three-dimensional (3D) shear wave velocity (Vs) model of the crust and uppermost mantle beneath Portugal, inferred from ambient seismic noise tomography. We use broadband seismic data from a dense temporary deployment covering the entire Portuguese mainland between 2010 and 2012 in the scope of the WILAS project. Vertical component data are processed using phase correlation and phase weighted stack to obtain Empirical Green functions (EGF) for 3900 station pairs. Further, we use a random sampling and subset stacking strategy to measure robust Rayleigh wave group velocities in the period range 7-30 s and associated uncertainties. The tomographic inversion is performed in 2 steps: First, we determine group velocity lateral variations for each period. Next, we invert them at each grid point using a new trans-dimensional inversion scheme to obtain the 3D shear wave velocity model. The final 3D model extends from the upper crust (5 km) down to the uppermost mantle (60 km) and has a lateral resolution of similar to 50 km. In the upper and middle crust, the Vs anomaly pattern matches the tectonic units of the variscan massif and alpine basins. The transition between the Lusitanian Basin and the Ossa Morena Zone is marked by a contrast between moderate and high velocity anomalies, in addition to two arched earthquake lineations. Some faults, namely the Manteigas-Vilarica-Braganca fault and the Porto-Tomar-Ferreira do Alentejo fault, have a clear signature from the upper crust down to the uppermost mantle (60 km). Our 3D shear wave velocity model offers new insights into the continuation of the main tectonic units at depth and contributes to better understanding the seismicity of Portugal.Oxford University PressRCIPLSilveira, GraçaDias, NunoKiselev, SergeyStutzmann, EleonoreCustodio, SusanaSchimmel, Martin2023-05-23T07:52:00Z2022-04-222022-04-22T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/10400.21/16104engSILVEIRA, Graça.; [et al] – Imaging the crust and uppermost mantle structure of Portugal (West Iberia) with seismic ambient noise. Geophysical Journal International. ISSN 0956-540X. Vol. 230, N.º 2 (2022), pp. 1106-1120.0956-540X10.1093/gji/ggac1061365-246Xmetadata only accessinfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-08-03T10:14:25Zoai:repositorio.ipl.pt:10400.21/16104Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T20:23:42.076577Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Imaging the crust and uppermost mantle structure of Portugal (West Iberia) with seismic ambient noise |
title |
Imaging the crust and uppermost mantle structure of Portugal (West Iberia) with seismic ambient noise |
spellingShingle |
Imaging the crust and uppermost mantle structure of Portugal (West Iberia) with seismic ambient noise Silveira, Graça Seismic interferometry Surface waves and free oscillations Seismic tomography Crustal imaging Crustal structure |
title_short |
Imaging the crust and uppermost mantle structure of Portugal (West Iberia) with seismic ambient noise |
title_full |
Imaging the crust and uppermost mantle structure of Portugal (West Iberia) with seismic ambient noise |
title_fullStr |
Imaging the crust and uppermost mantle structure of Portugal (West Iberia) with seismic ambient noise |
title_full_unstemmed |
Imaging the crust and uppermost mantle structure of Portugal (West Iberia) with seismic ambient noise |
title_sort |
Imaging the crust and uppermost mantle structure of Portugal (West Iberia) with seismic ambient noise |
author |
Silveira, Graça |
author_facet |
Silveira, Graça Dias, Nuno Kiselev, Sergey Stutzmann, Eleonore Custodio, Susana Schimmel, Martin |
author_role |
author |
author2 |
Dias, Nuno Kiselev, Sergey Stutzmann, Eleonore Custodio, Susana Schimmel, Martin |
author2_role |
author author author author author |
dc.contributor.none.fl_str_mv |
RCIPL |
dc.contributor.author.fl_str_mv |
Silveira, Graça Dias, Nuno Kiselev, Sergey Stutzmann, Eleonore Custodio, Susana Schimmel, Martin |
dc.subject.por.fl_str_mv |
Seismic interferometry Surface waves and free oscillations Seismic tomography Crustal imaging Crustal structure |
topic |
Seismic interferometry Surface waves and free oscillations Seismic tomography Crustal imaging Crustal structure |
description |
We present a new high-resolution three-dimensional (3D) shear wave velocity (Vs) model of the crust and uppermost mantle beneath Portugal, inferred from ambient seismic noise tomography. We use broadband seismic data from a dense temporary deployment covering the entire Portuguese mainland between 2010 and 2012 in the scope of the WILAS project. Vertical component data are processed using phase correlation and phase weighted stack to obtain Empirical Green functions (EGF) for 3900 station pairs. Further, we use a random sampling and subset stacking strategy to measure robust Rayleigh wave group velocities in the period range 7-30 s and associated uncertainties. The tomographic inversion is performed in 2 steps: First, we determine group velocity lateral variations for each period. Next, we invert them at each grid point using a new trans-dimensional inversion scheme to obtain the 3D shear wave velocity model. The final 3D model extends from the upper crust (5 km) down to the uppermost mantle (60 km) and has a lateral resolution of similar to 50 km. In the upper and middle crust, the Vs anomaly pattern matches the tectonic units of the variscan massif and alpine basins. The transition between the Lusitanian Basin and the Ossa Morena Zone is marked by a contrast between moderate and high velocity anomalies, in addition to two arched earthquake lineations. Some faults, namely the Manteigas-Vilarica-Braganca fault and the Porto-Tomar-Ferreira do Alentejo fault, have a clear signature from the upper crust down to the uppermost mantle (60 km). Our 3D shear wave velocity model offers new insights into the continuation of the main tectonic units at depth and contributes to better understanding the seismicity of Portugal. |
publishDate |
2022 |
dc.date.none.fl_str_mv |
2022-04-22 2022-04-22T00:00:00Z 2023-05-23T07:52:00Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10400.21/16104 |
url |
http://hdl.handle.net/10400.21/16104 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
SILVEIRA, Graça.; [et al] – Imaging the crust and uppermost mantle structure of Portugal (West Iberia) with seismic ambient noise. Geophysical Journal International. ISSN 0956-540X. Vol. 230, N.º 2 (2022), pp. 1106-1120. 0956-540X 10.1093/gji/ggac106 1365-246X |
dc.rights.driver.fl_str_mv |
metadata only access info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
metadata only access |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Oxford University Press |
publisher.none.fl_str_mv |
Oxford University Press |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
instname_str |
Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
repository.mail.fl_str_mv |
|
_version_ |
1799133509502107648 |