Controls on the erosion of the continental margin of southeast Brazil from cosmogenic Be-10 in river sediments
Autor(a) principal: | |
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Data de Publicação: | 2019 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://dx.doi.org/10.1016/j.geomorph.2019.01.020 http://hdl.handle.net/11449/184414 |
Resumo: | The Atlantic Ocean coast region of southeast Brazil contains two coast-parallel mountain ranges (the Serra do Mar and Serra da Mantiqueira) generated by tectonic activity pulses tens of millions years after the main continental rift event occurred around 120 Ma. Although the short-term erosion rates for the region are established, the relative importance of the factors controlling erosion is poorly constrained. We combine new and published catchment-averaged erosion rates (n = 48) using in situ-produced Be-10 concentrations in quartz from river sediments to establish the regional erosion pattern. The river catchments are (i) escarpment topography, (ii) high-altitude low-relief and (iii) mixed topography, which record how escarpment fronts are migrating inland. Ocean-facing coastal escarpment catchments of the Serra do Mar (epsilon = 18-53 m/Ma) can be eroded approximately twice as fast as continent-facing escarpment catchments in the Serra do Mar and Serra da Mantiqueira (epsilon = 7-24 m/Ma). The correlation between the normalized channel steepness index (k(sn)) and slope angle indicates that river incision and hillslope erosion processes combine to maintain the high relief. The Serra do Mar catchments define a mean slope angle threshold indicating that landslides are the dominant erosional process when slope angles in excess of similar to 30 degrees Tectonic activity is low and plays no significant role in driving erosion. A first-order relationship between erosion rate and precipitation-temperature across the region implies that climate plays a key role in soil production, river incision and in triggering erosional processes. Although the high topographic relief is a pre-condition for the occurrence of significant erosion, the climatic condition is the outlining factor of the regional variation in erosion rates. (C) 2019 Elsevier B.V. All rights reserved. |
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Controls on the erosion of the continental margin of southeast Brazil from cosmogenic Be-10 in river sedimentsSerra do MarSerra da MantiqueiraEscarpment retreatPassive marginThe Atlantic Ocean coast region of southeast Brazil contains two coast-parallel mountain ranges (the Serra do Mar and Serra da Mantiqueira) generated by tectonic activity pulses tens of millions years after the main continental rift event occurred around 120 Ma. Although the short-term erosion rates for the region are established, the relative importance of the factors controlling erosion is poorly constrained. We combine new and published catchment-averaged erosion rates (n = 48) using in situ-produced Be-10 concentrations in quartz from river sediments to establish the regional erosion pattern. The river catchments are (i) escarpment topography, (ii) high-altitude low-relief and (iii) mixed topography, which record how escarpment fronts are migrating inland. Ocean-facing coastal escarpment catchments of the Serra do Mar (epsilon = 18-53 m/Ma) can be eroded approximately twice as fast as continent-facing escarpment catchments in the Serra do Mar and Serra da Mantiqueira (epsilon = 7-24 m/Ma). The correlation between the normalized channel steepness index (k(sn)) and slope angle indicates that river incision and hillslope erosion processes combine to maintain the high relief. The Serra do Mar catchments define a mean slope angle threshold indicating that landslides are the dominant erosional process when slope angles in excess of similar to 30 degrees Tectonic activity is low and plays no significant role in driving erosion. A first-order relationship between erosion rate and precipitation-temperature across the region implies that climate plays a key role in soil production, river incision and in triggering erosional processes. Although the high topographic relief is a pre-condition for the occurrence of significant erosion, the climatic condition is the outlining factor of the regional variation in erosion rates. (C) 2019 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Univ Estadual Paulista, Inst Geociencias & Ciencias Exacts, Ave 24A,1515, BR-13506900 Rio Claro, BrazilScottish Univ Environm Res Ctr, Rankine Ave, East Klibride G75 0QF, ScotlandUniv Fed Sao Paulo, Dept Ciencias Ambientais, Rua Sao Nicolau 210, BR-09913030 Diadema, BrazilUniv Estadual Paulista, Inst Geociencias & Ciencias Exacts, Ave 24A,1515, BR-13506900 Rio Claro, BrazilCAPES: 99999.002505/2015-00CAPES: 2014/23334-4Elsevier B.V.Universidade Estadual Paulista (Unesp)Scottish Univ Environm Res CtrUniversidade Federal de São Paulo (UNIFESP)Souza, Daniel H. de [UNESP]Stuart, Finlay M.Rodes, AngelPupim, Fabiano N.Hackspacher, Peter C. [UNESP]2019-10-04T11:57:43Z2019-10-04T11:57:43Z2019-04-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article163-176http://dx.doi.org/10.1016/j.geomorph.2019.01.020Geomorphology. Amsterdam: Elsevier Science Bv, v. 330, p. 163-176, 2019.0169-555Xhttp://hdl.handle.net/11449/18441410.1016/j.geomorph.2019.01.020WOS:00046140750001410401359359087340000-0003-2125-3050Web of Sciencereponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengGeomorphologyinfo:eu-repo/semantics/openAccess2021-10-23T01:35:32Zoai:repositorio.unesp.br:11449/184414Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-08-05T18:23:41.481833Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
Controls on the erosion of the continental margin of southeast Brazil from cosmogenic Be-10 in river sediments |
title |
Controls on the erosion of the continental margin of southeast Brazil from cosmogenic Be-10 in river sediments |
spellingShingle |
Controls on the erosion of the continental margin of southeast Brazil from cosmogenic Be-10 in river sediments Souza, Daniel H. de [UNESP] Serra do Mar Serra da Mantiqueira Escarpment retreat Passive margin |
title_short |
Controls on the erosion of the continental margin of southeast Brazil from cosmogenic Be-10 in river sediments |
title_full |
Controls on the erosion of the continental margin of southeast Brazil from cosmogenic Be-10 in river sediments |
title_fullStr |
Controls on the erosion of the continental margin of southeast Brazil from cosmogenic Be-10 in river sediments |
title_full_unstemmed |
Controls on the erosion of the continental margin of southeast Brazil from cosmogenic Be-10 in river sediments |
title_sort |
Controls on the erosion of the continental margin of southeast Brazil from cosmogenic Be-10 in river sediments |
author |
Souza, Daniel H. de [UNESP] |
author_facet |
Souza, Daniel H. de [UNESP] Stuart, Finlay M. Rodes, Angel Pupim, Fabiano N. Hackspacher, Peter C. [UNESP] |
author_role |
author |
author2 |
Stuart, Finlay M. Rodes, Angel Pupim, Fabiano N. Hackspacher, Peter C. [UNESP] |
author2_role |
author author author author |
dc.contributor.none.fl_str_mv |
Universidade Estadual Paulista (Unesp) Scottish Univ Environm Res Ctr Universidade Federal de São Paulo (UNIFESP) |
dc.contributor.author.fl_str_mv |
Souza, Daniel H. de [UNESP] Stuart, Finlay M. Rodes, Angel Pupim, Fabiano N. Hackspacher, Peter C. [UNESP] |
dc.subject.por.fl_str_mv |
Serra do Mar Serra da Mantiqueira Escarpment retreat Passive margin |
topic |
Serra do Mar Serra da Mantiqueira Escarpment retreat Passive margin |
description |
The Atlantic Ocean coast region of southeast Brazil contains two coast-parallel mountain ranges (the Serra do Mar and Serra da Mantiqueira) generated by tectonic activity pulses tens of millions years after the main continental rift event occurred around 120 Ma. Although the short-term erosion rates for the region are established, the relative importance of the factors controlling erosion is poorly constrained. We combine new and published catchment-averaged erosion rates (n = 48) using in situ-produced Be-10 concentrations in quartz from river sediments to establish the regional erosion pattern. The river catchments are (i) escarpment topography, (ii) high-altitude low-relief and (iii) mixed topography, which record how escarpment fronts are migrating inland. Ocean-facing coastal escarpment catchments of the Serra do Mar (epsilon = 18-53 m/Ma) can be eroded approximately twice as fast as continent-facing escarpment catchments in the Serra do Mar and Serra da Mantiqueira (epsilon = 7-24 m/Ma). The correlation between the normalized channel steepness index (k(sn)) and slope angle indicates that river incision and hillslope erosion processes combine to maintain the high relief. The Serra do Mar catchments define a mean slope angle threshold indicating that landslides are the dominant erosional process when slope angles in excess of similar to 30 degrees Tectonic activity is low and plays no significant role in driving erosion. A first-order relationship between erosion rate and precipitation-temperature across the region implies that climate plays a key role in soil production, river incision and in triggering erosional processes. Although the high topographic relief is a pre-condition for the occurrence of significant erosion, the climatic condition is the outlining factor of the regional variation in erosion rates. (C) 2019 Elsevier B.V. All rights reserved. |
publishDate |
2019 |
dc.date.none.fl_str_mv |
2019-10-04T11:57:43Z 2019-10-04T11:57:43Z 2019-04-01 |
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://dx.doi.org/10.1016/j.geomorph.2019.01.020 Geomorphology. Amsterdam: Elsevier Science Bv, v. 330, p. 163-176, 2019. 0169-555X http://hdl.handle.net/11449/184414 10.1016/j.geomorph.2019.01.020 WOS:000461407500014 1040135935908734 0000-0003-2125-3050 |
url |
http://dx.doi.org/10.1016/j.geomorph.2019.01.020 http://hdl.handle.net/11449/184414 |
identifier_str_mv |
Geomorphology. Amsterdam: Elsevier Science Bv, v. 330, p. 163-176, 2019. 0169-555X 10.1016/j.geomorph.2019.01.020 WOS:000461407500014 1040135935908734 0000-0003-2125-3050 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Geomorphology |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
163-176 |
dc.publisher.none.fl_str_mv |
Elsevier B.V. |
publisher.none.fl_str_mv |
Elsevier B.V. |
dc.source.none.fl_str_mv |
Web of Science reponame:Repositório Institucional da UNESP instname:Universidade Estadual Paulista (UNESP) instacron:UNESP |
instname_str |
Universidade Estadual Paulista (UNESP) |
instacron_str |
UNESP |
institution |
UNESP |
reponame_str |
Repositório Institucional da UNESP |
collection |
Repositório Institucional da UNESP |
repository.name.fl_str_mv |
Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP) |
repository.mail.fl_str_mv |
|
_version_ |
1808128926978932736 |