Incised valleys on the Algarve inner shelf, northern Gulf of Cadiz margin: stratigraphic architecture and controlling factors in a low fluvial supply setting
Autor(a) principal: | |
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Data de Publicação: | 2023 |
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/10400.1/20133 |
Resumo: | A network of cross-shelf paleovalleys has been recognized over the paleo-inner shelf off the Gila & SIM;o-Almargem Estuary, a small fluvial drainage system that presently receives minor sediment supply in the eastern Algarve shelf, northern margin of the Gulf of Cadiz (SW Iberian Peninsula). This study is aimed at determining the driving controls that triggered substantially different paleohydrological conditions and sedimentary dynamics of ancient fluvial systems in this margin. We focus on evidences of secondary controls on valley genesis and evolution, superimposed to primary glacio-eustatic control such as antecedent geology, low fluvial supply and changing hydrodynamic regimes. The architecture and spatial distribution of these paleovalleys were interpreted based on a grid of seismic profiles with different resolutions. Likewise, a sediment core obtained in a distal position of the paleovalley system provided information about sedimentary processes during the most recent stage of valley infilling. The chronostratigraphic framework was constructed based on regional seismic horizons defined in previous studies and complemented with two AMS 14C dates obtained from bivalve shells.The inner shelf paleovalley system is composed of several incised valley features which exhibit a remarkable similar internal architecture. These inner valley features exhibit two major incision phases (from oldest to youngest; IP 2 and IP 1) that are thought to constitute a simple paleovalley system formed during the last glacial cycle. The origins of the incision are considered to be different. The older one is related to fluvial incision during the sea-level fall leading into the Last Glacial Maximum, whereas the recent one is interpreted as the result of tidal scour during the postglacial transgression. Their corresponding infillings are interpreted, respectively, as estuarine bay-fill deposits and estuary-mouth sands. Overlying the paleovalley infilling, a distinctive reflective unit is in agreement with the generation of coastal barriers and related depositional systems.The formation of the paleo-inner-shelf paleovalley system was strongly conditioned by antecedent geology, which strongly limited the generation of wide incised valleys and determined the amount of incision landward of a well-defined break of slope. Its postglacial infilling was mainly estuarine in nature, likely involving the development of a dendritic system, with numerous barriers interrupted by tidal inlets and channels in a mixed estuarine system with low fluvial supply. |
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Incised valleys on the Algarve inner shelf, northern Gulf of Cadiz margin: stratigraphic architecture and controlling factors in a low fluvial supply settingGulf of CadizSeismic stratigraphyPaleovalleysContinental shelfFluvial incisionTidal inletsA network of cross-shelf paleovalleys has been recognized over the paleo-inner shelf off the Gila & SIM;o-Almargem Estuary, a small fluvial drainage system that presently receives minor sediment supply in the eastern Algarve shelf, northern margin of the Gulf of Cadiz (SW Iberian Peninsula). This study is aimed at determining the driving controls that triggered substantially different paleohydrological conditions and sedimentary dynamics of ancient fluvial systems in this margin. We focus on evidences of secondary controls on valley genesis and evolution, superimposed to primary glacio-eustatic control such as antecedent geology, low fluvial supply and changing hydrodynamic regimes. The architecture and spatial distribution of these paleovalleys were interpreted based on a grid of seismic profiles with different resolutions. Likewise, a sediment core obtained in a distal position of the paleovalley system provided information about sedimentary processes during the most recent stage of valley infilling. The chronostratigraphic framework was constructed based on regional seismic horizons defined in previous studies and complemented with two AMS 14C dates obtained from bivalve shells.The inner shelf paleovalley system is composed of several incised valley features which exhibit a remarkable similar internal architecture. These inner valley features exhibit two major incision phases (from oldest to youngest; IP 2 and IP 1) that are thought to constitute a simple paleovalley system formed during the last glacial cycle. The origins of the incision are considered to be different. The older one is related to fluvial incision during the sea-level fall leading into the Last Glacial Maximum, whereas the recent one is interpreted as the result of tidal scour during the postglacial transgression. Their corresponding infillings are interpreted, respectively, as estuarine bay-fill deposits and estuary-mouth sands. Overlying the paleovalley infilling, a distinctive reflective unit is in agreement with the generation of coastal barriers and related depositional systems.The formation of the paleo-inner-shelf paleovalley system was strongly conditioned by antecedent geology, which strongly limited the generation of wide incised valleys and determined the amount of incision landward of a well-defined break of slope. Its postglacial infilling was mainly estuarine in nature, likely involving the development of a dendritic system, with numerous barriers interrupted by tidal inlets and channels in a mixed estuarine system with low fluvial supply.Research projects CGL2011-30302-C02-02 and PID2021-125489OB-I00, supported by Spanish Ministries of Economy and Competitiveness and Science and Innovation. LA/P/0069/2020ElsevierSapientiaCarrión-Torrente, ÁlvaroLobo, Francisco JoséPuga-Bernabéu, ÁngelLuján, MaríaMendes, IsabelHanebuth, Till J. J.Lebreiro, SusanaGarcía, MargaReguera, María IsabelAntón, LauraVan Rooij, DavidCerrillo-Escoriza, Javier2023-11-07T10:34:14Z2023-092023-09-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/10400.1/20133eng10.1016/j.csr.2023.1050951873-6955info: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:RCAAP2023-11-15T02:00:33Zoai:sapientia.ualg.pt:10400.1/20133Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T21:26:57.379315Repositório 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 |
Incised valleys on the Algarve inner shelf, northern Gulf of Cadiz margin: stratigraphic architecture and controlling factors in a low fluvial supply setting |
title |
Incised valleys on the Algarve inner shelf, northern Gulf of Cadiz margin: stratigraphic architecture and controlling factors in a low fluvial supply setting |
spellingShingle |
Incised valleys on the Algarve inner shelf, northern Gulf of Cadiz margin: stratigraphic architecture and controlling factors in a low fluvial supply setting Carrión-Torrente, Álvaro Gulf of Cadiz Seismic stratigraphy Paleovalleys Continental shelf Fluvial incision Tidal inlets |
title_short |
Incised valleys on the Algarve inner shelf, northern Gulf of Cadiz margin: stratigraphic architecture and controlling factors in a low fluvial supply setting |
title_full |
Incised valleys on the Algarve inner shelf, northern Gulf of Cadiz margin: stratigraphic architecture and controlling factors in a low fluvial supply setting |
title_fullStr |
Incised valleys on the Algarve inner shelf, northern Gulf of Cadiz margin: stratigraphic architecture and controlling factors in a low fluvial supply setting |
title_full_unstemmed |
Incised valleys on the Algarve inner shelf, northern Gulf of Cadiz margin: stratigraphic architecture and controlling factors in a low fluvial supply setting |
title_sort |
Incised valleys on the Algarve inner shelf, northern Gulf of Cadiz margin: stratigraphic architecture and controlling factors in a low fluvial supply setting |
author |
Carrión-Torrente, Álvaro |
author_facet |
Carrión-Torrente, Álvaro Lobo, Francisco José Puga-Bernabéu, Ángel Luján, María Mendes, Isabel Hanebuth, Till J. J. Lebreiro, Susana García, Marga Reguera, María Isabel Antón, Laura Van Rooij, David Cerrillo-Escoriza, Javier |
author_role |
author |
author2 |
Lobo, Francisco José Puga-Bernabéu, Ángel Luján, María Mendes, Isabel Hanebuth, Till J. J. Lebreiro, Susana García, Marga Reguera, María Isabel Antón, Laura Van Rooij, David Cerrillo-Escoriza, Javier |
author2_role |
author author author author author author author author author author author |
dc.contributor.none.fl_str_mv |
Sapientia |
dc.contributor.author.fl_str_mv |
Carrión-Torrente, Álvaro Lobo, Francisco José Puga-Bernabéu, Ángel Luján, María Mendes, Isabel Hanebuth, Till J. J. Lebreiro, Susana García, Marga Reguera, María Isabel Antón, Laura Van Rooij, David Cerrillo-Escoriza, Javier |
dc.subject.por.fl_str_mv |
Gulf of Cadiz Seismic stratigraphy Paleovalleys Continental shelf Fluvial incision Tidal inlets |
topic |
Gulf of Cadiz Seismic stratigraphy Paleovalleys Continental shelf Fluvial incision Tidal inlets |
description |
A network of cross-shelf paleovalleys has been recognized over the paleo-inner shelf off the Gila & SIM;o-Almargem Estuary, a small fluvial drainage system that presently receives minor sediment supply in the eastern Algarve shelf, northern margin of the Gulf of Cadiz (SW Iberian Peninsula). This study is aimed at determining the driving controls that triggered substantially different paleohydrological conditions and sedimentary dynamics of ancient fluvial systems in this margin. We focus on evidences of secondary controls on valley genesis and evolution, superimposed to primary glacio-eustatic control such as antecedent geology, low fluvial supply and changing hydrodynamic regimes. The architecture and spatial distribution of these paleovalleys were interpreted based on a grid of seismic profiles with different resolutions. Likewise, a sediment core obtained in a distal position of the paleovalley system provided information about sedimentary processes during the most recent stage of valley infilling. The chronostratigraphic framework was constructed based on regional seismic horizons defined in previous studies and complemented with two AMS 14C dates obtained from bivalve shells.The inner shelf paleovalley system is composed of several incised valley features which exhibit a remarkable similar internal architecture. These inner valley features exhibit two major incision phases (from oldest to youngest; IP 2 and IP 1) that are thought to constitute a simple paleovalley system formed during the last glacial cycle. The origins of the incision are considered to be different. The older one is related to fluvial incision during the sea-level fall leading into the Last Glacial Maximum, whereas the recent one is interpreted as the result of tidal scour during the postglacial transgression. Their corresponding infillings are interpreted, respectively, as estuarine bay-fill deposits and estuary-mouth sands. Overlying the paleovalley infilling, a distinctive reflective unit is in agreement with the generation of coastal barriers and related depositional systems.The formation of the paleo-inner-shelf paleovalley system was strongly conditioned by antecedent geology, which strongly limited the generation of wide incised valleys and determined the amount of incision landward of a well-defined break of slope. Its postglacial infilling was mainly estuarine in nature, likely involving the development of a dendritic system, with numerous barriers interrupted by tidal inlets and channels in a mixed estuarine system with low fluvial supply. |
publishDate |
2023 |
dc.date.none.fl_str_mv |
2023-11-07T10:34:14Z 2023-09 2023-09-01T00:00:00Z |
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/10400.1/20133 |
url |
http://hdl.handle.net/10400.1/20133 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1016/j.csr.2023.105095 1873-6955 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Elsevier |
publisher.none.fl_str_mv |
Elsevier |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
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RCAAP |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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1799134151101644800 |