Gravity anomalies over extinct spreading centres: A new evidence of an aborted ridge in the South Atlantic Ocean
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/10.1093/gji/ggz019 http://hdl.handle.net/11449/190370 |
Resumo: | An aborted ridge has been suggested in the Vema region, South Atlantic Ocean, and we investigate it in terms of residual gravity anomalies and half spreading rate. Gravity signature over extinct spreading centres displays residual gravity anomaly lows flanked by positive highs with systematic palaeo-spreading rate dependency. The amplitude and half-widths of the gravity lows are smaller for fast spreading rates, a relationship that has been presented for several well-constrained extinct spreading centres, such as Coral Sea and Labrador Sea, both regarded in this work for comparative purposes. The residual gravity anomalies are estimated from the removal of a long-wavelength regional trend and the gravitational effect of basement and suprabasement sources. The global sediment thickness model of NOAA is used to evaluate the sediment layer and a compaction model that fits observed density values is also considered. The basement topography is obtained from gravity field inversion and shows clearly the extinct spreading axes of the Coral Sea Basin and Labrador Sea, which are not evident from the bathymetric data set due to sedimentary deposits that lie over them. The Vema basement shows an NS structure previously suggested as the Vema Aborted Ridge (VAR), which does not coincide with the morphological feature known as the Vema Channel. Over the VAR, we have found amplitudes and half-widths in function of their half spreading rate typical from well-constrained extinct spreading centres, indicating that the structure might actually be an aborted ridge. |
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Gravity anomalies over extinct spreading centres: A new evidence of an aborted ridge in the South Atlantic OceanAtlantic OceanGravity anomalies and Earth structureSatellite gravitySubmarine tectonics and volcanismAn aborted ridge has been suggested in the Vema region, South Atlantic Ocean, and we investigate it in terms of residual gravity anomalies and half spreading rate. Gravity signature over extinct spreading centres displays residual gravity anomaly lows flanked by positive highs with systematic palaeo-spreading rate dependency. The amplitude and half-widths of the gravity lows are smaller for fast spreading rates, a relationship that has been presented for several well-constrained extinct spreading centres, such as Coral Sea and Labrador Sea, both regarded in this work for comparative purposes. The residual gravity anomalies are estimated from the removal of a long-wavelength regional trend and the gravitational effect of basement and suprabasement sources. The global sediment thickness model of NOAA is used to evaluate the sediment layer and a compaction model that fits observed density values is also considered. The basement topography is obtained from gravity field inversion and shows clearly the extinct spreading axes of the Coral Sea Basin and Labrador Sea, which are not evident from the bathymetric data set due to sedimentary deposits that lie over them. The Vema basement shows an NS structure previously suggested as the Vema Aborted Ridge (VAR), which does not coincide with the morphological feature known as the Vema Channel. Over the VAR, we have found amplitudes and half-widths in function of their half spreading rate typical from well-constrained extinct spreading centres, indicating that the structure might actually be an aborted ridge.Institute of Geosciences and Exact Sciences São Paulo State University - UNESPGeological Survey of Brazil - CPRM/DISEGEInstitute of Astronomy Geophysics and Atmospheric Sciences University of São Paulo - USPInstitute of Geosciences and Exact Sciences São Paulo State University - UNESP/UNESPetroInstitute of Geosciences and Exact Sciences São Paulo State University - UNESPInstitute of Geosciences and Exact Sciences São Paulo State University - UNESP/UNESPetroUniversidade Estadual Paulista (Unesp)Geological Survey of Brazil - CPRM/DISEGEUniversidade de São Paulo (USP)Constantino, Renata Regina [UNESP]Hackspacher, Peter Christian [UNESP]Costa, Iago Sousa LimaMolina, Eder CassolaDe Souza, Iata Anderson [UNESP]2019-10-06T17:11:00Z2019-10-06T17:11:00Z2019-01-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article361-374http://dx.doi.org/10.1093/gji/ggz019Geophysical Journal International, v. 217, n. 1, p. 361-374, 2019.1365-246X0956-540Xhttp://hdl.handle.net/11449/19037010.1093/gji/ggz0192-s2.0-8506673178810401359359087340000-0003-2125-3050Scopusreponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengGeophysical Journal Internationalinfo:eu-repo/semantics/openAccess2021-10-23T18:56:51Zoai:repositorio.unesp.br:11449/190370Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-08-05T16:32:56.541370Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
Gravity anomalies over extinct spreading centres: A new evidence of an aborted ridge in the South Atlantic Ocean |
title |
Gravity anomalies over extinct spreading centres: A new evidence of an aborted ridge in the South Atlantic Ocean |
spellingShingle |
Gravity anomalies over extinct spreading centres: A new evidence of an aborted ridge in the South Atlantic Ocean Constantino, Renata Regina [UNESP] Atlantic Ocean Gravity anomalies and Earth structure Satellite gravity Submarine tectonics and volcanism |
title_short |
Gravity anomalies over extinct spreading centres: A new evidence of an aborted ridge in the South Atlantic Ocean |
title_full |
Gravity anomalies over extinct spreading centres: A new evidence of an aborted ridge in the South Atlantic Ocean |
title_fullStr |
Gravity anomalies over extinct spreading centres: A new evidence of an aborted ridge in the South Atlantic Ocean |
title_full_unstemmed |
Gravity anomalies over extinct spreading centres: A new evidence of an aborted ridge in the South Atlantic Ocean |
title_sort |
Gravity anomalies over extinct spreading centres: A new evidence of an aborted ridge in the South Atlantic Ocean |
author |
Constantino, Renata Regina [UNESP] |
author_facet |
Constantino, Renata Regina [UNESP] Hackspacher, Peter Christian [UNESP] Costa, Iago Sousa Lima Molina, Eder Cassola De Souza, Iata Anderson [UNESP] |
author_role |
author |
author2 |
Hackspacher, Peter Christian [UNESP] Costa, Iago Sousa Lima Molina, Eder Cassola De Souza, Iata Anderson [UNESP] |
author2_role |
author author author author |
dc.contributor.none.fl_str_mv |
Universidade Estadual Paulista (Unesp) Geological Survey of Brazil - CPRM/DISEGE Universidade de São Paulo (USP) |
dc.contributor.author.fl_str_mv |
Constantino, Renata Regina [UNESP] Hackspacher, Peter Christian [UNESP] Costa, Iago Sousa Lima Molina, Eder Cassola De Souza, Iata Anderson [UNESP] |
dc.subject.por.fl_str_mv |
Atlantic Ocean Gravity anomalies and Earth structure Satellite gravity Submarine tectonics and volcanism |
topic |
Atlantic Ocean Gravity anomalies and Earth structure Satellite gravity Submarine tectonics and volcanism |
description |
An aborted ridge has been suggested in the Vema region, South Atlantic Ocean, and we investigate it in terms of residual gravity anomalies and half spreading rate. Gravity signature over extinct spreading centres displays residual gravity anomaly lows flanked by positive highs with systematic palaeo-spreading rate dependency. The amplitude and half-widths of the gravity lows are smaller for fast spreading rates, a relationship that has been presented for several well-constrained extinct spreading centres, such as Coral Sea and Labrador Sea, both regarded in this work for comparative purposes. The residual gravity anomalies are estimated from the removal of a long-wavelength regional trend and the gravitational effect of basement and suprabasement sources. The global sediment thickness model of NOAA is used to evaluate the sediment layer and a compaction model that fits observed density values is also considered. The basement topography is obtained from gravity field inversion and shows clearly the extinct spreading axes of the Coral Sea Basin and Labrador Sea, which are not evident from the bathymetric data set due to sedimentary deposits that lie over them. The Vema basement shows an NS structure previously suggested as the Vema Aborted Ridge (VAR), which does not coincide with the morphological feature known as the Vema Channel. Over the VAR, we have found amplitudes and half-widths in function of their half spreading rate typical from well-constrained extinct spreading centres, indicating that the structure might actually be an aborted ridge. |
publishDate |
2019 |
dc.date.none.fl_str_mv |
2019-10-06T17:11:00Z 2019-10-06T17:11:00Z 2019-01-01 |
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/10.1093/gji/ggz019 Geophysical Journal International, v. 217, n. 1, p. 361-374, 2019. 1365-246X 0956-540X http://hdl.handle.net/11449/190370 10.1093/gji/ggz019 2-s2.0-85066731788 1040135935908734 0000-0003-2125-3050 |
url |
http://dx.doi.org/10.1093/gji/ggz019 http://hdl.handle.net/11449/190370 |
identifier_str_mv |
Geophysical Journal International, v. 217, n. 1, p. 361-374, 2019. 1365-246X 0956-540X 10.1093/gji/ggz019 2-s2.0-85066731788 1040135935908734 0000-0003-2125-3050 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Geophysical Journal International |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
361-374 |
dc.source.none.fl_str_mv |
Scopus 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_ |
1808128670179524608 |