Superposed deformation straddling the continental-oceanic transition in deep-water Angola
Autor(a) principal: | |
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Data de Publicação: | 2000 |
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/10284/200 |
Resumo: | The Angolan margin is the type area for raft tectonics. New seismic data reveal the contractional buffer for this thin-skinned extension. A 200-km-long composite section from the Lower Congo Basin and Kwanza Basin illustrates a complex history of superposed deformation caused by: (1) progradation of the margin; and (2) episodic Tertiary epeirogenic uplift. Late Cretaceous tectonics was driven by a gentle slope created by thermal subsidence; extensional rafting took place updip, contractional thrusting and buckling downdip; some distal folds were possibly unroofed to form massive salt walls. Oligocene deformation was triggered by gentle kinking of the Atlantic Hinge Zone as the shelf and coastal plain rose by 2 or 3 km; relative uplift stripped Paleogene cover off the shelf, provided space for Miocene progradation, and steepened the continental slope, triggering more extension and buckling. In the Neogene, a subsalt half graben was inverted or reactivated, creating keystone faults that may have controlled the Congo Canyon; a thrust duplex of seaward-displaced salt jacked up the former abyssal plain, creating a plateau of salt 3–4 km thick on the present lower slope. The Angola Escarpment may be the toe of the Angola thrust nappe, in which a largely Cretaceous roof of gently buckled strata, was transported seawards above the thickened salt by up to ,20 km. q 2001 Elsevier Science Ltd. All rights reserved. |
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Superposed deformation straddling the continental-oceanic transition in deep-water AngolaAngolaBasin evolutionCongo CanyonFold-and-thrust beltGravity tectonicsKwanza BasinLower Congo BasinRaft tectonicsSalt tectonicsThe Angolan margin is the type area for raft tectonics. New seismic data reveal the contractional buffer for this thin-skinned extension. A 200-km-long composite section from the Lower Congo Basin and Kwanza Basin illustrates a complex history of superposed deformation caused by: (1) progradation of the margin; and (2) episodic Tertiary epeirogenic uplift. Late Cretaceous tectonics was driven by a gentle slope created by thermal subsidence; extensional rafting took place updip, contractional thrusting and buckling downdip; some distal folds were possibly unroofed to form massive salt walls. Oligocene deformation was triggered by gentle kinking of the Atlantic Hinge Zone as the shelf and coastal plain rose by 2 or 3 km; relative uplift stripped Paleogene cover off the shelf, provided space for Miocene progradation, and steepened the continental slope, triggering more extension and buckling. In the Neogene, a subsalt half graben was inverted or reactivated, creating keystone faults that may have controlled the Congo Canyon; a thrust duplex of seaward-displaced salt jacked up the former abyssal plain, creating a plateau of salt 3–4 km thick on the present lower slope. The Angola Escarpment may be the toe of the Angola thrust nappe, in which a largely Cretaceous roof of gently buckled strata, was transported seawards above the thickened salt by up to ,20 km. q 2001 Elsevier Science Ltd. All rights reserved.ElsevierRepositório Institucional da Universidade Fernando PessoaCramez, CarlosJackson, M. P. A.2006-05-15T10:55:47Z2000-01-01T00:00:00Z2000-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article1758442 bytesapplication/pdfapplication/pdfhttp://hdl.handle.net/10284/200engMarine and Petroleum Geology, Vol. 17, nº10, pp. 1095-1109info: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:RCAAP2022-09-06T02:00:22Zoai:bdigital.ufp.pt:10284/200Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T15:38:12.385813Repositório 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 |
Superposed deformation straddling the continental-oceanic transition in deep-water Angola |
title |
Superposed deformation straddling the continental-oceanic transition in deep-water Angola |
spellingShingle |
Superposed deformation straddling the continental-oceanic transition in deep-water Angola Cramez, Carlos Angola Basin evolution Congo Canyon Fold-and-thrust belt Gravity tectonics Kwanza Basin Lower Congo Basin Raft tectonics Salt tectonics |
title_short |
Superposed deformation straddling the continental-oceanic transition in deep-water Angola |
title_full |
Superposed deformation straddling the continental-oceanic transition in deep-water Angola |
title_fullStr |
Superposed deformation straddling the continental-oceanic transition in deep-water Angola |
title_full_unstemmed |
Superposed deformation straddling the continental-oceanic transition in deep-water Angola |
title_sort |
Superposed deformation straddling the continental-oceanic transition in deep-water Angola |
author |
Cramez, Carlos |
author_facet |
Cramez, Carlos Jackson, M. P. A. |
author_role |
author |
author2 |
Jackson, M. P. A. |
author2_role |
author |
dc.contributor.none.fl_str_mv |
Repositório Institucional da Universidade Fernando Pessoa |
dc.contributor.author.fl_str_mv |
Cramez, Carlos Jackson, M. P. A. |
dc.subject.por.fl_str_mv |
Angola Basin evolution Congo Canyon Fold-and-thrust belt Gravity tectonics Kwanza Basin Lower Congo Basin Raft tectonics Salt tectonics |
topic |
Angola Basin evolution Congo Canyon Fold-and-thrust belt Gravity tectonics Kwanza Basin Lower Congo Basin Raft tectonics Salt tectonics |
description |
The Angolan margin is the type area for raft tectonics. New seismic data reveal the contractional buffer for this thin-skinned extension. A 200-km-long composite section from the Lower Congo Basin and Kwanza Basin illustrates a complex history of superposed deformation caused by: (1) progradation of the margin; and (2) episodic Tertiary epeirogenic uplift. Late Cretaceous tectonics was driven by a gentle slope created by thermal subsidence; extensional rafting took place updip, contractional thrusting and buckling downdip; some distal folds were possibly unroofed to form massive salt walls. Oligocene deformation was triggered by gentle kinking of the Atlantic Hinge Zone as the shelf and coastal plain rose by 2 or 3 km; relative uplift stripped Paleogene cover off the shelf, provided space for Miocene progradation, and steepened the continental slope, triggering more extension and buckling. In the Neogene, a subsalt half graben was inverted or reactivated, creating keystone faults that may have controlled the Congo Canyon; a thrust duplex of seaward-displaced salt jacked up the former abyssal plain, creating a plateau of salt 3–4 km thick on the present lower slope. The Angola Escarpment may be the toe of the Angola thrust nappe, in which a largely Cretaceous roof of gently buckled strata, was transported seawards above the thickened salt by up to ,20 km. q 2001 Elsevier Science Ltd. All rights reserved. |
publishDate |
2000 |
dc.date.none.fl_str_mv |
2000-01-01T00:00:00Z 2000-01-01T00:00:00Z 2006-05-15T10:55:47Z |
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/10284/200 |
url |
http://hdl.handle.net/10284/200 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Marine and Petroleum Geology, Vol. 17, nº10, pp. 1095-1109 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
1758442 bytes application/pdf application/pdf |
dc.publisher.none.fl_str_mv |
Elsevier |
publisher.none.fl_str_mv |
Elsevier |
dc.source.none.fl_str_mv |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
institution |
RCAAP |
reponame_str |
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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