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dc.contributor.authorSánchez Moreno, Elisa María 
dc.contributor.authorCalvo Rathert, Manuel 
dc.contributor.authorGoguitchaichvili, Avto
dc.contributor.authorTauxe, Lisa .
dc.contributor.authorVashakidze, George T.
dc.contributor.authorLebedev, Vladimir A.
dc.date.accessioned2021-11-05T09:14:10Z
dc.date.available2021-11-05T09:14:10Z
dc.date.issued2020-03
dc.identifier.issn1365-246X
dc.identifier.urihttp://hdl.handle.net/10259/6108
dc.description.abstractA palaeointensity study has been carried out on a Pliocene sequence of 20 consecutive lava flows where previous directional results seem to reflect anomalous behaviour of the Earth’s magnetic field (EMF), which can be explained by a polarity transition record or non-averaged palaeosecular variation or both. Here, we perform a total of 55 palaeointensity determinations using the original Thellier–Thellier (TT) method and 100 with the IZZI method.We assess the performance of our selection criteria using a set of strict threshold values applied to a set of test data whose TRMs were acquired in known fields. Absolute palaeointensity determinations that passed our selection criteria were obtained on four specimens with the TT method and on 41 specimens with the IZZI method. Application of reliability criteria at a site level yielded palaeointensity results in 8 of 20 studied lava flows. We obtained median values of VADM between 28.9 and 45.6 ZAm2 for the reverse polarity lower Apnia section, while the normal polarity upper section displayed a single value of 54.6 ZAm2. The low palaeointensity values before a transitional direction lava flow and the higher value after it, suggest the common behaviour at the start of a polarity reversal and the recovery after it. However, an isolated record of a stable EMF, where the intensity is lower than the current for the same location (83.7 ZAm2), cannot be discarded. Consequently, this interpretation would support a weak time-averaged field.en
dc.description.sponsorshipProject CGL2012-32149 (Ministerio de Economía y Competitividad, Spain), project BU066U16 (Junta de Castilla y León, Spain), pre-doctoral grant BES-2013-064060 (Ministerio de Economía y Competitividad, Spain) and by National Science Foundation (USA) grant EAR1345003.en
dc.format.mimetypeapplication/pdf
dc.language.isoenges
dc.publisherOxford University Pressen
dc.relation.ispartofGeophysical Journal International. V. 220, n. 3, p. 1604–1618en
dc.subjectPalaeointensityen
dc.subjectMagnetic field variations through timeen
dc.subjectPalaeomagnetismen
dc.subject.otherMagnetismoes
dc.subject.otherMagnetismen
dc.subject.otherGeologíaes
dc.subject.otherGeologyen
dc.titleWeak palaeointensity results over a Pliocene volcanic sequence from Lesser Caucasus (Georgia): transitional record or time averaged field?en
dc.typeinfo:eu-repo/semantics/articlees
dc.rights.accessRightsinfo:eu-repo/semantics/openAccesses
dc.relation.publisherversionhttps://doi.org/10.1093/gji/ggz533
dc.identifier.doi10.1093/gji/ggz533
dc.relation.projectIDinfo:eu-repo/grantAgreement/MINECO//CGL2012-32149/ES/VARIACION DE LA PALEOINTENSIDAD ABSOLUTA DEL CAMPO MAGNETICO TERRESTRE REGISTRADA EN ROCAS VOLCANICAS: MOMENTO DIPOLAR, TRANSICIONES DE POLARIDAD Y SUPERCRONESes
dc.relation.projectIDinfo:eu-repo/grantAgreement/Junta de Castilla y León//BU066U16//Estudio arqueomagnéticos y de propiedades magnéticas en registros de fuegos antrópicos prehistóricos. Aplicaciones a la arqueologíaes
dc.relation.projectIDinfo:eu-repo/grantAgreement/MINECO//BES-2013-064060es
dc.relation.projectIDinfo:eu-repo/grantAgreement/NSF//EAR1345003es
dc.type.hasVersioninfo:eu-repo/semantics/publishedVersiones


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