Publicación:
Control of seasonal and inter-annual rainfall distribution on the Strontium-Neodymium isotopic compositions of suspended particulate matter and implications for tracing ENSO events in the Pacific coast (Tumbes basin, Peru)

dc.contributor.author Moquet J.-S. es_PE
dc.contributor.author Morera S.B. es_PE
dc.contributor.author Turcq B. es_PE
dc.contributor.author Poitrasson F. es_PE
dc.contributor.author Roddaz M. es_PE
dc.contributor.author Moreira-Turcq P. es_PE
dc.contributor.author Espinoza J.C. es_PE
dc.contributor.author Guyot J.-L. es_PE
dc.contributor.author Takahashi K. es_PE
dc.contributor.author Orrillo J.D. es_PE
dc.contributor.author Petrick S. es_PE
dc.contributor.author Mounic S. es_PE
dc.contributor.author Sondag F. es_PE
dc.date.accessioned 2024-05-30T23:13:38Z
dc.date.available 2024-05-30T23:13:38Z
dc.date.issued 2020
dc.description.abstract The geochemistry of riverine sediments exported to the oceans is important for paleo-hydro-climatic reconstruction. However, climate reconstruction requires a good understanding of the relationship between geochemistry and hydrological variability and sediment sources. In this study, we analyzed the major elements, the strontium-neodymium radiogenic isotopes signatures (87Sr/86Sr and ?Nd) and the mineralogy of the suspended particulate matter (SPM) sampled monthly during two hydrologic years (2007–2008, a wet year, and 2010–2011, a normal hydrological year) upstream the Tumbes River outlet. The hydroclimate of this Ecuador-Peru binational basin is particularly sensitive to ENSO (El Niño Southern Oscillation) events. While mineralogy (dominated by illite) and the chemical alteration index (from 75 to 82) remain almost constant along the two hydrological years, 87Sr/86Sr (0.7115 to 0.7176) and ?Nd (?7.8 to ?1.9) signatures are particularly sensitive to discharge and SPM concentration variations. Along the hydrological year, two sources control the ?Nd variability: (1) volcanic rocks, which dominate during the dry season, and (2) plutonic/metamorphic sources, whose contribution increases during the wet season. This behavior is confirmed by the correlation between ?Nd signature and the monthly rainfall contribution from volcanic area (R = 0.58; p-value < 0.01), and also with the daily discharge at the outlet (R = -0.73; p-value < 0.01). For most of the samples, 87Sr/86Sr is less variable along the hydrological year. However, two exceptional high discharge and SPM concentration conditions sampled exhibit more radiogenic (higher) 87Sr/86Sr signatures when plutonic/metamorphic rocks derived sediments are released in sufficient quantities to notably change the SPM isotopic Sr value of the Tumbes River. Hence, this study demonstrates that 87Sr/86Sr and ?Nd signatures can be used as powerful proxies for paleoclimate reconstructions based on sediment core's analysis in relation with spatial rainfall distribution and intensity in Pacific sedimentary basins submitted to the diversity of ENSO events. © 2019 Elsevier B.V.
dc.description.sponsorship Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concytec
dc.identifier.doi https://doi.org/10.1016/j.gloplacha.2019.103080
dc.identifier.scopus 2-s2.0-85075485904
dc.identifier.uri https://hdl.handle.net/20.500.12390/2660
dc.language.iso eng
dc.publisher Elsevier B.V.
dc.relation.ispartof Global and Planetary Change
dc.rights info:eu-repo/semantics/openAccess
dc.rights.uri https://creativecommons.org/licenses/by-nc-nd/4.0/
dc.subject Suspended sediments
dc.subject Andes es_PE
dc.subject Hydrology es_PE
dc.subject Pacific basin es_PE
dc.subject River es_PE
dc.subject Sr and Nd radiogenic isotopes es_PE
dc.subject.ocde http://purl.org/pe-repo/ocde/ford#1.05.09
dc.title Control of seasonal and inter-annual rainfall distribution on the Strontium-Neodymium isotopic compositions of suspended particulate matter and implications for tracing ENSO events in the Pacific coast (Tumbes basin, Peru)
dc.type info:eu-repo/semantics/article
dspace.entity.type Publication
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