%0 Journal Article
%@nexthigherunit 8JMKD3MGPCW/3F35TRS
%@nexthigherunit 8JMKD3MGPCW/46KUATE
%3 sousa_changes.pdf
%4 sid.inpe.br/mtc-m21c/2021/03.22.15.50
%8 May
%9 journal article
%@issn 0025-3227
%A Sousa, Thiago A. de,
%A Venancio, Igor Martins,
%A Valeriano, Cláudio de Morisson,
%A Heilbron, Monica,
%A Carneiro, Maria T. Weitzel Dias,
%A Mane, Miguel Angelo,
%A Almeida, Júlio C. Horta de,
%A Smoak, Joseph M.,
%A Albuquerque, Ana Luiza S.,
%A Silva Filho, Emmanoel Vieira,
%@secondarytype PRE PI
%B Marine Geology
%D 2021
%@archivingpolicy denypublisher denyfinaldraft24
%K Rare Earth Elements, Radiogenic isotopes, Marine sediments, Glacial/interglacial climate, Northeast Brazil.
%P e106454
%@secondarymark A1_GEOCIÊNCIAS A1_ENGENHARIAS_III A2_PLANEJAMENTO_URBANO_E_REGIONAL_/_DEMOGRAFIA A2_INTERDISCIPLINAR A2_CIÊNCIAS_AGRÁRIAS_I A2_BIODIVERSIDADE B1_QUÍMICA B1_FARMÁCIA B1_CIÊNCIAS_BIOLÓGICAS_I B1_BIOTECNOLOGIA B2_ENSINO
%T Changes in sedimentary provenance and climate off the coast of Northeast Brazil since the Last Interglacial
%V 435
%X Neodymium (Nd) and strontium (Sr) isotopic signatures in marine sediments reflect the geology of the associated drainage basin from which those sediments are supplied. These signatures are significantly affected by relief, weathering, transport, and deposition of sedimentary contributions from the respective sources. This work makes available new data of SrNd isotope ratios and Rare Earth Element (REE) concentrations, which provides a record of the sedimentary provenance of marine sediment supplied to the continental slope off the coast of northeastern Brazil since the last 130 thousand years. Our results indicate the main source of sediments to this site was the Parnaíba sedimentary basin. Furthermore, the fluctuations in Fe/K, Al/Si ratios, and Sr values are explained by geochemical processes operating within the region, which likely reflects changes in the hydrological regime and relative sea-level, and intensity of weathering in continental rocks in glacial-interglacial timescales. We suggest that low values of 87Sr/86Sr ratios during glacial are a result of dry conditions. Also, minor fluctuations within the last glacial period may be a consequence of displacements of the Intertropical Convergence Zone (ITCZ). Such displacements cause changes in rainfall and consequently variations in chemical weathering which affect Sr isotopic fractionation. During past humid intervals, the low Nd (non-radiogenic) signal observed could be explained as a process of penetration of rainwater into the deepest non-radiogenic sediment and subsequent replacement of the isotopic signal in the environment in glacial-interglacial timescales.
%@area MET
%@electronicmailaddress tasousa.geo@gmail.com
%@electronicmailaddress igor.venancio@inpe.br
%@documentstage not transferred
%@group
%@group MET-MET-DIPGR-INPE-MCTI-GOV-BR
%@dissemination WEBSCI; PORTALCAPES.
%@usergroup simone
%@affiliation Universidade Federal Fluminense (UFF)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Universidade do Estado do Rio de Janeiro (UERJ)
%@affiliation Universidade do Estado do Rio de Janeiro (UERJ)
%@affiliation Universidade Federal do Espírito Santo (UFES)
%@affiliation Universidade do Estado do Rio de Janeiro (UERJ)
%@affiliation Universidade do Estado do Rio de Janeiro (UERJ)
%@affiliation University of South Florida
%@affiliation Universidade Federal Fluminense (UFF)
%@affiliation Universidade Federal Fluminense (UFF)
%@versiontype publisher
%@holdercode {isadg {BR SPINPE} ibi 8JMKD3MGPCW/3DT298S}
%@doi 10.1016/j.margeo.2021.106454
%2 sid.inpe.br/mtc-m21c/2021/03.22.15.50.56