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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.

The Doñana National Park is a Biosphere Reserve located within the estuary of the Guadalquivir River (SW Spain). It is mainly composed of extensive fluvio-tidal marshes partially protected by an elongated sandy spit. Three phases have been distinguished in the late Holocene evolution of this spit based on textural, geochemical, palaeontological and, chronological data recorded in a long core (31 m). Phase 1 (890 BCE-218 BCE) is characterized by the alternation of lagoonal silty sediments and slightly polluted marsh deposits, the latter with contamination from thousand-year-old mining. Phase 2 (218 BCE-90 CE) is characterized by several historical tsunamis, which caused the erosion of previous dune systems and the deposit of these sandy sediments on the adjacent bottom of the lagoon. Phase 3 (90 CE-Present) includes a regressive sequence (lagoonal bottom-marsh-dune system), with the pollution of lagoonal sediments due to Roman mining activities.

This paper focuses on a residual ancient aeolian climbing dune from Punta Penaboa (A Coruña, Northwest Spain) showing evidence of post-depositional weathering, particularly the presence of dark brown nodular masses. The partitioning of trace elements between nodular masses and host sand during post-depositional weathering of the dune is investigated in this work, with the main objective of studying the elemental enrichment patterns in the dark masses. Data of the concentrations of chemical elements were obtained by instrumental neutron activation analysis (INAA) and complemented by mineralogical and microchemical studies, using X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) / energy dispersive X-ray spectrometry (EDS). The dune was dated by optically stimulated luminescence (OSL) , yielding an age of 300ka B.P.. The dark nodular masses preserved the dune sand structure, without defined concentric layers, suggesting an early stage of formation. They consist mainly of quartz grains cemented by clay materials enriched in the majority of the elements studied, especially in Mn, Co, Ba, Sb, Ce, Tb, Th, As, Zr and Hf. The post-depositional transformations of the dune were most likely influenced by migration of chemical compounds from the surrounding slope deposits and granitic rocks, as well as microbial activity that promoted metals concentration in the solutions percolating through the pore network of the dune. Seasonal changes in the redox potential were required to produce the accumulation of Mn and other trace elements in the dune pore network and to promote the fractionation between Ce4+ and trivalent rare earth elements that was observed in the geochemical patterns

Numerous investigations have used the foraminiferal assemblages or species as bioindicators. This paper tests the responses of these microorganisms to different environmental changes (heavy metal pollution, treatment stations, artificial inlets, agricultural and urban sewages) and compares them to those observed previously on ostracod assemblages. Foraminifera are more tolerant to these changes, while ostracods present a more specialized response., Numerosas investigaciones han utilizado a las asociaciones o especies de foraminíferos como bioindicadores. Este trabajo investiga la respuesta de estos microorganismos ante diferentes cambios ambientales (contaminación por metales pesados, estaciones de tratamiento de residuos, pasajes artificiales, desechos urbanos e industriales) y la compara con la observada previamente en las asociaciones de ostrácodos. Los foraminíferos son más tolerantes a estos cambios, en tanto que la respuesta de los ostrácodos es más especializada.

La Pijotilla es uno de los mayores asentamientos (80 Ha) del III milenio A.N.E. de la Península Ibérica, siendo considerado un lugar central dentro de la red de poblamiento de Tierra de Barros (comarca de Tierra de Barros, Badajoz). Desde los años 70 se han excavado el poblado y la necrópolis, destacando la tumba T3, excavada en la roca donde se realizaron 300 inhumaciones en capas sucesivas generando una estratigrafía amplia y que contenía un variado y cuantioso ajuar. En el poblado se ha recuperado una colección de fragmentos campaniformes sin contexto estratigráfico, junto a una gran diversidad de estilos decorativos pertenecientes a la última fases del III milenio ANE. El objetivo propuesto en este trabajo ha sido datar diferentes niveles de la tumba T3 y compararlas con otras dataciones C14; al igual que datar la cerámica campaniforme de superficie del poblado y compararla con dataciones absolutas procedentes de contextos habitacionales, La Pijotilla, one of the largest settlements through out all Iberian Peninsula, and is considered a central place of Tierra de Barros Copper Age settlement network (Comarca de Tierra de Barros, Badajoz). During the field works that has been going on since the 70’s, the settlement and the necropolis area have been located. Several tombs have been excavated, standing out tomb 3, build on the rock with 300 buried individuals and a great richness of funerary objects alternated in several layers. During survey works in the settlement a large amount of decorated pottery from III millennium BC including a great number of Bell Beaker pottery, without a stratigraphic context, have been found. The focus in this work is to date different layers of T3 using luminescence techniques and compare them with old and new radiocarbon dates, as well as to date the survey-collected Bell Beaker pottery and compare them with the settlement radiocarbon dates