Gravity anomalies over extinct spreading centres: A new evidence of an aborted ridge in the South Atlantic Ocean

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dc.contributor.authorConstantino, Renata Regina [UNESP]
dc.contributor.authorHackspacher, Peter Christian [UNESP]
dc.contributor.authorCosta, Iago Sousa Lima
dc.contributor.authorMolina, Eder Cassola
dc.contributor.authorDe Souza, Iata Anderson [UNESP]
dc.contributor.institutionUniversidade Estadual Paulista (Unesp)
dc.contributor.institutionGeological Survey of Brazil - CPRM/DISEGE
dc.contributor.institutionUniversidade de São Paulo (USP)
dc.date.accessioned2019-10-06T17:11:00Z
dc.date.available2019-10-06T17:11:00Z
dc.date.issued2019-01-01
dc.description.abstractAn 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.en
dc.description.affiliationInstitute of Geosciences and Exact Sciences São Paulo State University - UNESP
dc.description.affiliationGeological Survey of Brazil - CPRM/DISEGE
dc.description.affiliationInstitute of Astronomy Geophysics and Atmospheric Sciences University of São Paulo - USP
dc.description.affiliationInstitute of Geosciences and Exact Sciences São Paulo State University - UNESP/UNESPetro
dc.description.affiliationUnespInstitute of Geosciences and Exact Sciences São Paulo State University - UNESP
dc.description.affiliationUnespInstitute of Geosciences and Exact Sciences São Paulo State University - UNESP/UNESPetro
dc.format.extent361-374
dc.identifierhttp://dx.doi.org/10.1093/gji/ggz019
dc.identifier.citationGeophysical Journal International, v. 217, n. 1, p. 361-374, 2019.
dc.identifier.doi10.1093/gji/ggz019
dc.identifier.issn1365-246X
dc.identifier.issn0956-540X
dc.identifier.lattes1040135935908734
dc.identifier.orcid0000-0003-2125-3050
dc.identifier.scopus2-s2.0-85066731788
dc.identifier.urihttp://hdl.handle.net/11449/190370
dc.language.isoeng
dc.relation.ispartofGeophysical Journal International
dc.rights.accessRightsAcesso aberto
dc.sourceScopus
dc.subjectAtlantic Ocean
dc.subjectGravity anomalies and Earth structure
dc.subjectSatellite gravity
dc.subjectSubmarine tectonics and volcanism
dc.titleGravity anomalies over extinct spreading centres: A new evidence of an aborted ridge in the South Atlantic Oceanen
dc.typeArtigo
unesp.author.lattes1040135935908734[2]
unesp.author.orcid0000-0003-2125-3050[2]

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