Middle-Late Permian magnetostratigraphy and the onset of the Illawarra Reversals in the northeastern Parana Basin, South America
Autor(a) principal: | |
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Data de Publicação: | 2021 |
Outros Autores: | |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://dx.doi.org/10.1093/gji/ggab011 http://hdl.handle.net/11449/206247 |
Resumo: | Recent compilations of the Illawarra Reversals show remarkable differences in the onset age (265 Ma versus 269 Ma) and the magnetic polarity pattern, hampering the establishment of a reference geomagnetic timescale for the Middle-Late Permian. The Parana Basin hosts a 7-km-thick, discontinuous sedimentary succession spanning the Palaeozoic to the Mesozoic, including the Gondwana 1 supersequence which extends from Late Carboniferous to the Triassic or Jurassic. We provide the magnetostratigraphy of the middle and upper Permian part of this sequence of a ca. 300-m-long core, pertaining to the Passa Dois Group and the Piramboia Formation. Sample demagnetization of NRM revealed two magnetic overprints ascribed to the Brunhes chron and to the emplacement of Parana Large Igneous Province in the Early Cretaceous, respectively. Stable, dual polarity characteristic components (ChRM) were isolated at temperatures higher than 450 °C and interpreted as a primary detrital magnetic remanence (DRM), acquired during or soon after sediment deposition. Available U-Pb dating on volcanic zircons from the literature provided independent chronologic constraints for our magnetostratigraphy. A total of 8 reverse polarity intervals were identified, the lowermost of which (up to 110 m thick) correlates to the Kiaman Superchron. The overlying Illawarra is dominated by a reverse polarity magnetization with thin (4-5 m thick) normal polarity intervals. This pattern agrees with the Illawarra sequence from the Karoo Basin and other proposed timescales for the Permian. The onset of the Illawarra reversals is interpolated to ca. 270 Ma, close to the age of 269 Ma from the Karoo Basin. Combined magnetostratigraphy and geochronology yielded sediment accumulation rates of ca. 8 m Myr-1 for the Passa Dois Group in the northeastern (marginal) sector of the Parana Basin, indicating that Serra Alta and Teresina Formations span 279-274 Ma and 274-254 Ma, respectively. |
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Middle-Late Permian magnetostratigraphy and the onset of the Illawarra Reversals in the northeastern Parana Basin, South AmericaMagnetostratigraphyPalaeomagnetismSouth AmericaRecent compilations of the Illawarra Reversals show remarkable differences in the onset age (265 Ma versus 269 Ma) and the magnetic polarity pattern, hampering the establishment of a reference geomagnetic timescale for the Middle-Late Permian. The Parana Basin hosts a 7-km-thick, discontinuous sedimentary succession spanning the Palaeozoic to the Mesozoic, including the Gondwana 1 supersequence which extends from Late Carboniferous to the Triassic or Jurassic. We provide the magnetostratigraphy of the middle and upper Permian part of this sequence of a ca. 300-m-long core, pertaining to the Passa Dois Group and the Piramboia Formation. Sample demagnetization of NRM revealed two magnetic overprints ascribed to the Brunhes chron and to the emplacement of Parana Large Igneous Province in the Early Cretaceous, respectively. Stable, dual polarity characteristic components (ChRM) were isolated at temperatures higher than 450 °C and interpreted as a primary detrital magnetic remanence (DRM), acquired during or soon after sediment deposition. Available U-Pb dating on volcanic zircons from the literature provided independent chronologic constraints for our magnetostratigraphy. A total of 8 reverse polarity intervals were identified, the lowermost of which (up to 110 m thick) correlates to the Kiaman Superchron. The overlying Illawarra is dominated by a reverse polarity magnetization with thin (4-5 m thick) normal polarity intervals. This pattern agrees with the Illawarra sequence from the Karoo Basin and other proposed timescales for the Permian. The onset of the Illawarra reversals is interpolated to ca. 270 Ma, close to the age of 269 Ma from the Karoo Basin. Combined magnetostratigraphy and geochronology yielded sediment accumulation rates of ca. 8 m Myr-1 for the Passa Dois Group in the northeastern (marginal) sector of the Parana Basin, indicating that Serra Alta and Teresina Formations span 279-274 Ma and 274-254 Ma, respectively.Universidade Estadual Paulista (UNESP) Instituto de Geociências e Ciências ExatasUniversidade Estadual Paulista (UNESP) Instituto de Geociências e Ciências ExatasUniversidade Estadual Paulista (Unesp)Aragão, Marcela [UNESP]Scardia, Giancarlo [UNESP]2021-06-25T10:29:01Z2021-06-25T10:29:01Z2021-05-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article860-871http://dx.doi.org/10.1093/gji/ggab011Geophysical Journal International, v. 225, n. 2, p. 860-871, 2021.1365-246X0956-540Xhttp://hdl.handle.net/11449/20624710.1093/gji/ggab0112-s2.0-85104888647Scopusreponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengGeophysical Journal Internationalinfo:eu-repo/semantics/openAccess2021-10-23T01:57:54Zoai:repositorio.unesp.br:11449/206247Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-08-05T16:23:50.228645Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
Middle-Late Permian magnetostratigraphy and the onset of the Illawarra Reversals in the northeastern Parana Basin, South America |
title |
Middle-Late Permian magnetostratigraphy and the onset of the Illawarra Reversals in the northeastern Parana Basin, South America |
spellingShingle |
Middle-Late Permian magnetostratigraphy and the onset of the Illawarra Reversals in the northeastern Parana Basin, South America Aragão, Marcela [UNESP] Magnetostratigraphy Palaeomagnetism South America |
title_short |
Middle-Late Permian magnetostratigraphy and the onset of the Illawarra Reversals in the northeastern Parana Basin, South America |
title_full |
Middle-Late Permian magnetostratigraphy and the onset of the Illawarra Reversals in the northeastern Parana Basin, South America |
title_fullStr |
Middle-Late Permian magnetostratigraphy and the onset of the Illawarra Reversals in the northeastern Parana Basin, South America |
title_full_unstemmed |
Middle-Late Permian magnetostratigraphy and the onset of the Illawarra Reversals in the northeastern Parana Basin, South America |
title_sort |
Middle-Late Permian magnetostratigraphy and the onset of the Illawarra Reversals in the northeastern Parana Basin, South America |
author |
Aragão, Marcela [UNESP] |
author_facet |
Aragão, Marcela [UNESP] Scardia, Giancarlo [UNESP] |
author_role |
author |
author2 |
Scardia, Giancarlo [UNESP] |
author2_role |
author |
dc.contributor.none.fl_str_mv |
Universidade Estadual Paulista (Unesp) |
dc.contributor.author.fl_str_mv |
Aragão, Marcela [UNESP] Scardia, Giancarlo [UNESP] |
dc.subject.por.fl_str_mv |
Magnetostratigraphy Palaeomagnetism South America |
topic |
Magnetostratigraphy Palaeomagnetism South America |
description |
Recent compilations of the Illawarra Reversals show remarkable differences in the onset age (265 Ma versus 269 Ma) and the magnetic polarity pattern, hampering the establishment of a reference geomagnetic timescale for the Middle-Late Permian. The Parana Basin hosts a 7-km-thick, discontinuous sedimentary succession spanning the Palaeozoic to the Mesozoic, including the Gondwana 1 supersequence which extends from Late Carboniferous to the Triassic or Jurassic. We provide the magnetostratigraphy of the middle and upper Permian part of this sequence of a ca. 300-m-long core, pertaining to the Passa Dois Group and the Piramboia Formation. Sample demagnetization of NRM revealed two magnetic overprints ascribed to the Brunhes chron and to the emplacement of Parana Large Igneous Province in the Early Cretaceous, respectively. Stable, dual polarity characteristic components (ChRM) were isolated at temperatures higher than 450 °C and interpreted as a primary detrital magnetic remanence (DRM), acquired during or soon after sediment deposition. Available U-Pb dating on volcanic zircons from the literature provided independent chronologic constraints for our magnetostratigraphy. A total of 8 reverse polarity intervals were identified, the lowermost of which (up to 110 m thick) correlates to the Kiaman Superchron. The overlying Illawarra is dominated by a reverse polarity magnetization with thin (4-5 m thick) normal polarity intervals. This pattern agrees with the Illawarra sequence from the Karoo Basin and other proposed timescales for the Permian. The onset of the Illawarra reversals is interpolated to ca. 270 Ma, close to the age of 269 Ma from the Karoo Basin. Combined magnetostratigraphy and geochronology yielded sediment accumulation rates of ca. 8 m Myr-1 for the Passa Dois Group in the northeastern (marginal) sector of the Parana Basin, indicating that Serra Alta and Teresina Formations span 279-274 Ma and 274-254 Ma, respectively. |
publishDate |
2021 |
dc.date.none.fl_str_mv |
2021-06-25T10:29:01Z 2021-06-25T10:29:01Z 2021-05-01 |
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/ggab011 Geophysical Journal International, v. 225, n. 2, p. 860-871, 2021. 1365-246X 0956-540X http://hdl.handle.net/11449/206247 10.1093/gji/ggab011 2-s2.0-85104888647 |
url |
http://dx.doi.org/10.1093/gji/ggab011 http://hdl.handle.net/11449/206247 |
identifier_str_mv |
Geophysical Journal International, v. 225, n. 2, p. 860-871, 2021. 1365-246X 0956-540X 10.1093/gji/ggab011 2-s2.0-85104888647 |
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 |
860-871 |
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 |
|
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1808128642837905408 |