REE geochemistry of neogene–holocene sediments of La Fontanilla Cove (Tinto Estuary, SW Spain)

The Tinto and Odiel rivers (SW Spain) drain from a vast sulfide mining district and join at a 20-km-long estuary that enters the Atlantic Ocean. In this work, the contents of rare earth elements (REE) and fractionation in Neogene–Holocene sediment cores from La Fontanilla cove (Tinto estuary) were s...

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Detalles Bibliográficos
Autores: Prudêncio, Maria Isabel, Ruiz, Francisco, Marques, Rosa, Dias, Maria Isabel, Rodriguez Vidal, Joaquín, Rodrigues, Ana Luisa, Cáceres, Luis Miguel, González-Regalado, María Luz, Muñoz, Juan Manuel, Pozo Rodríguez, Manuel, Gómez, Paula, Toscano, Antonio, Abad, Manuel, Izquierdo, Tatiana, Arroyo, Marta, Romero, Verónica, Gómez, Gabriel
Tipo de recurso: artículo
Fecha de publicación:2022
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/705351
Acceso en línea:http://hdl.handle.net/10486/705351
https://dx.doi.org/10.3390/min12040417
Access Level:acceso abierto
Palabra clave:rare earth elements
estuarine sediments cores
sedimentary facies
acid drainage
paleoenvironmental reconstruction
Tinto River
Geología
Descripción
Sumario:The Tinto and Odiel rivers (SW Spain) drain from a vast sulfide mining district and join at a 20-km-long estuary that enters the Atlantic Ocean. In this work, the contents of rare earth elements (REE) and fractionation in Neogene–Holocene sediment cores from La Fontanilla cove (Tinto estuary) were studied. The sediments were collected from a depth of 18 m at different distances from the recent river flow and were analyzed for new information on the temporal development of the REE load in the sediment column. Results show that the ∑ REE is higher in the finer sediments and during periods of mining activity from prehistoric to recent times. Marine influence appears to increase the light REE (LREE) relative to the heavy REE (HREE). The REE patterns of these estuarine sediments show convex curvatures in the MREE relative to the LREE and HREE, indicating the presence of acid-mixing processes between the fluvial waters affected by acid mine drainage (AMD) and seawater, as well as the precipitation of poorly crystalline mineral phases. Significant positive Eu anomalies were found in ebb-tide channels and marsh deposits, which can reflect the mineralogical composition and/or a strong localized salinity gradient combined with organic matter degradation. Sedimentological characteristics of the deposits appear to play the main role in accumulation and fractionation of the REE