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This paper investigates the paleoenvironmental evolution of a long core extracted in a small cove located in the Tinto-Odiel estuary (SW Spain). The inferred reconstruction is supported by sedimentological, geochemical, paleontological data and dating. Seven phases have been identified, with the transit from Late Neogene marine environments to a subrecent freshwater pond and a final anthropic filling. On the basis of these data, this area was flooded during the maximum of the MIS-1 transgression (6.5-5.2 cal. kyr BP), with the temporary presence of a subtidal channel with phanerogam meadows. During this evolution, three geochemical peaks have been detected, which correspond to 1) the first evidence of mining activities (~4.5 cal. kyr BP), 2) an interval of intensive mining (1850-1960) and 3) an industrial period (1966-1985), affected by the dumping of highly polluting waste into this estuary.

Portus was the main port of imperial Rome from the 2nd century AD to the 5th century AD, with an inner, hexagonal port (Trajan basin) and an outer port (Claudius basin) linked by a channel bounded by quays. Six sedimentary facies have been differentiated in the geological analysis of a core extracted in this channel, basically composed of poorly classified bioclastic muds typical of restricted environments, accumulations of Posidonia oceanica (Linnaeus) Delile, 1813 and a final anthropic fill. The subfossil record of bivalves, foraminifera and ostracods is characteristic of Mediterranean brackish environments (lagoons, estuaries, deltas) with significant environmental stress, due to changes in the physical-chemical parameters and probably the periodic dredging of this seaway during a period of about 300 years. The presence of “Neptune balls” points to the development of probable stormy periods that deposit these unique structures in the internal areas of this historic port.

This paper studies the malacofauna of four sediment cores collected in an old cove of the Tinto-Odiel estuary (SW Spain) to establish the chronology and spatial extent of MIS-1 transgression in this area. The paleoenvironmental interpretation based on facies analysis and the malacological record point to an evolution from a Miocene marine substrate to a final anthropic filling. During the late Pleistocene?-lower Holocene, this substrate was eroded by the fluvial network and alluvial sediments were deposited. During the maximum of the MIS-1 transgression (~ ca 6.5–5.4 kyr BP), this area was flooded and malacofauna is revealed as an excellent proxy of this transgression. Mesolittoral paleoenvironments dominated by the gastropod Peringia ulvae characterized the inner zones of the cove, while phanerogam meadows with abundant specimens of the gastropod Bittium reticulatum developed in the outermost areas. During the last 5400 years, this cove was progressively covered by marshes, although some mesolittoral paleoenvironments persisted until 4000 years BP.

Multivariate analyses have been applied to the REE contents of three cores collected in the Tinto estuary, SW Spain, an extremely polluted area. Results indicate an extremely correlation between all REE, which behave as a single variable. A slight natural pollution peak and three anthropogenic pollution peaks are identified, related with the first mining activities, the Roman period and a recent intensive mining accompanied by a heavy industrial pollution. In all these peaks, the increase of Cu is parallel to that of MREE, which are configured as the best indicators of pollution among REE. Statistical analyses clearly differentiate four groups, each consisting of samples from different environments. Although grain size and this strong pollution alter the study of REE as environmental indicators, it is possible to recognise groups of samples with a common origin or to identify the surface extent of a given pollution peak.

espanolEste trabajo analiza la evolucion vertical de facies y el contenido en Ag y Bi de un testigo continuo extraido en el estuario medio del rio Tinto (S.O. Espana). El analisis sedimentologico y paleontologico permite definir cuatro facies sedimentarias, caracteristicas de depositos aluviales (F1: 6,5-6,2 ka BP), la presencia de facies estuarinas durante la inundacion marina del sector coincidente con el maximo transgresivo holoceno y el periodo inmediatamente posterior (F2: 6,2-5,2 ka BP), el transito a marismas (F3: 5,2 ka BP-siglo XIX) y un relleno antropico de finales del siglo XX. Los contenidos de Ag y Bi permiten precisar tres periodos principales de contaminacion historica: i) inicio de las actividades mineras y explotacion de Ag durante la edad de Bronce (~4,5-3,2 ka BP); ii) periodo de maxima intensidad de la explotacion minera romana (siglos I-II DC); y iii) mineria intensiva reciente (desde 1870). EnglishThis paper analyzes the vertical evolution of facies and the Ag and Bi contents of a continuous core extracted in the middle estuary of the Tinto river (S.O. Spain). The sedimentological and paleontological analysis allows to define four sedimentary facies, characteristics of alluvial deposits (F1: 6.5-6.2 ka BP), the marine flooding of the sector during the maximum of the Holocene transgression and the period immediately after (F2: 6.2 -5.2 ka BP), the transition to marshes (F3: 5.2-19th century) and an anthropic landfill since the end of the 20th century. The concentrations of Ag and Bi make it possible to specify three main periods of historical contamination: i) the start of mining activities and the exploitation of Ag during the Bronze Age (~ 4.5-3.2 ka BP); ii) the period of maximum intensity of Roman mining (1st-2nd centuries DC); and iii) recent intensive mining (since 1870).

The multidisciplinary analysis (dating, texture, total mineralogy) of two deep cores collected in the Donana National Park (SW Spain) allows to distinguish the main features of three tsunami deposits found in three different paleoenvironmental scenarios (TSU-1: inner area of an open lagoon; TSU-2: inner area of a restricted lagoon; TSU- 3: outer area of a restricted lagoon). The main textural feature of the inner lagoonal tsunami deposits is the increase in bioclastic sands, while the outer TSU-3 is composed almost entirely of medium and fine sands without bioclasts. The mineralogical analysis of TSU-1 and TSU-2 reveals a decrease in phyllosilicates in the basal layers of these tsunami deposits and a parallel increase of quartz, feldspars, dolomite and sometimes calcite. Silica is the main component of TSU-3, whose mineralogical composition changes progressively due to the action of tidal currents in the inlet lagoon on which it is deposited. This rich- SiO2 outer tsunami deposit is derived from the erosion of the adjacent aeolian systems, while the inner TSU-1 and TSU-2 were generated by the transport of bioclastic sands from the outermost parts through the lagoon (TSU-1), or through a nearby tidal channel (TSU-2).

Las caráceas constituyen un grupo importante de macrófitos acuáticos en el Parque Nacional de Doñana. En este artículo, se estudia la distribución de sus girogonitos en diversos medios de este espacio protegido (lagunas temporales, surgencias, caños, márgenes del río Guadalquivir, etc), relacionándola tanto con las variables físico-químicas como con la textura y mineralogía del sedimento. Se efectúa una revisión del registro geológico de este grupo en diversos testigos compuestos por sedimentos pleistocenos y holocenos.

During the Neogene, the Betic Strait was one of the gateways that connected the Atlantic Ocean and the Mediterranean Sea. In this paper, we have analyzed the ostracod faunas of samples collected from sediments crossed by a long borehole in southwestern Spain. These sediments were deposited in the Betic strait just before the Messinian Salinity Crisis. During the middle Messinian (6.8-6.0 Ma), the scarce and low diversified ostracod assemblages (Krithe, Parakrithe, Henryhowella) are typical of upper bathyal palaeoenvironments (200-400 m water depth). This period includes a short transition (6.26-6.25 Ma) to outer neritic palaeoenvironments, coinciding with a glaciation and characterized by the presence of Acanthocythereis hystrix (Reuss, 1850) and the disappearance of Krithe and Parakrithe. The most abundant species have a wide biostratigraphic distribution, most of them ranging from the Tortonian until the Holocene.

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 analyzes the first systematic faunal record of the 1755 Lisbon tsunami in the Mediterranean. On the basis of sedimentological and paleontological features, the sedimentary record of a core collected in Gibraltar was divided into six sedimentary facies, with a paleoenvironmental evolution from a shallow marine paleoenviroment to an increasingly restricted lagoon. This record includes a bioclastic layer deposited by the 1755 Lisbon tsunami and characterized by an erosive base, presence of basal rip-up clasts and abundant shell debris composed by marine and brackish molluscs. The paleoenvironmental reconstruction derived from the foraminiferal analysis is congruent with that inferred from the sedimentary and the macrofaunal reconstructions, with the introduction of brackish species into the innermost, intertidal areas of a confined lagoon. This paleontological record is the first faunal evidence of the 1755 Lisbon tsunami in the Mediterranean., We thank the Gibraltar National Museum and its Director, Dr. Clive Finlayson, for the efforts made to conserve and acquire the BH borehole core. In addition, we thank the review of Dr. Akihisa Kitamura and Dr. Briony Mamo, whose suggestions greatly improved the manuscript, and the associate-editor of Geobios, Dr. Frédéric Quillévéré, for his kind help and comments during the revision process. This research was supported by two postdoctoral fellows of the Spanish Ministry of Science and Innovation Government (Subprograma JDCMICINN, JCI-2010-06160) and the Huelva University (PP2010 P-01). Furthermore, this work is carried out through DGYCIT project CTM2006-06722/MAR, DGYCIT project CGL2006-01412, FEDER 2014-2020 project UHU-126029, PID2021- 127268NB-I00 project funded by MCIN/ AEI /10.13039/50110 0011033/ and by FEDER, and AYUDA PUENTE 2021 project M2615 of the Rey Juan Carlos University. Other funds have come from the Andalusian Government (groups RNM-238, RNM-293 and RNM-349) and Autonomous University of Madrid (GPG-418 Research Group). It is a contribution to the Research Center in Historical, Cultural and Natural Heritage (CIPHCN) of the University of Huelva.

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 å 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, Funds came from the Andalusian Government (groups RNM-238 and RNM-293), the town hall of Palos de la Frontera, and the FEDER 2014–2020 project UHU-1260298, which is a contribution to the Research Center in Historical, Cultural, and Natural Heritage (CIPHCN) of the University of Huelva. The C2TN/IST authors gratefully acknowledge the support of the FCT (the Portuguese Science and Technology Foundation) through the UIDB/04349/2020 project and the post-doctoral grant SFRH/BPD/114986/2016

This paper presents the easternmost mineralogical and geochemical evidence of the 1755 Lisbon tsunami found in the Western Mediterranean. This multidisciplinary analysis of a sediment core obtained in Gibraltar (southern Iberian Peninsula) has allowed us to differentiate a tsunamiite from an old lagoon (The Inundation). This tsunamigenic layer has increased levels of calcite and aragonite and higher concentrations of Ba and ferromagnesian elements in comparison with the underlying lagoonal sediments of this core. This layer is also differentiated by its paleontological record, with the introduction of marine species within this lagoon. The uppermost part of the core includes a transition from swampy/marsh paleoenvironments to terrestrial scenarios, with a final anthropogenic filling occurring during the last century, This work was carried out through the following projects: a) DGYCIT project CTM2006- 06722/MAR; b) DGYCIT project CGL2006-01412; and c) FEDER 2014-2020 project UHU-1260298. Other funds have come from Autonomous University of Madrid (GPG-418 Research Group) and the Andalusian Government (groups RNM-238, RNM-293 and RNM-349). It is a contribution to the Research Center in Historical, Cultural and Natural Heritage (CIPHCN) of the University of Huelva

The southwestern Atlantic coast of the Iberian Peninsula presents an important Roman heritage that includes numerous fish-salting workshops, with an industrial activity that went on for almost a millennium (1st century BC-7th century AD). Nevertheless, a future broad research is still necessary to determine the geologic substratum on which they are based, their palaeoenvironmental evolution, their main economic objectives and the byproducts derived from their activities. This paper is focused on the geology, dating and the archaeological record of La Cascajera, a new site located in the Tinto-Odiel estuary (SW Spain). This new cetaria occupied the northwestern end of La Cascajera ridge (Saltés Island), constituted by sandy, bioclastic deposits of previous washover fans (1st-2th centuries AD). During the main period of activity (middle of 4th century AD-5th century AD), the existence of a certain typology of amphorae as well as the documentation of a shell deposit formed mostly by Glycymeris suggest that this factory was oriented to the production of mixed fish sauces and the handling of edible bivalves. The main features of this deposit (texture, paleontology, taphonomy) could be used to differentiate middens from natural shelly ridges, La costa suratlántica de la Península Ibérica posee un importante legado romano que incluye numerosos talleres halieúticos, con una actividad que se desarrolló durante casi un milenio (siglo I a.C.-siglo VII d.C.). Sin embargo, se precisan nuevas investigaciones que determinen el contexto geológico en el que se desarrollaron, su evolución paleoambiental, sus principales objetivos económicos y los subproductos derivados de sus actividades. Este trabajo se centra en la geología, datación y registro arqueológico de La Cascajera, un nuevo yacimiento localizado en el estuario de los ríos Tinto y Odiel (S.O. de España). Esta nueva cetaria ocupaba el extremo noroccidental de la cresta de La Cascajera (Isla de Saltés), constituida por depósitos bioclásticos arenosos de abanicos de derrame previos (siglos I-II d.C.). Durante su principal periodo de actividad (mitad del siglo IV d.C.-siglo V d.C.), la existencia de una cierta tipología de ánforas así como la existencia de un conchero formado principalmente por Glycymeris sugieren que esta factoría estaba dedicada a la producción de salsas mixtas de pescado y la extracción de bivalvos comestibles. Las principales características de este conchero (textura, paleontología, tafonomía) podrían ser usadas para diferenciar concheros de acumulaciones naturales de conchas, This work has been carried out through the project ́From the Atlantic to the Tyrrhenian. The hispanic ports and their commercial relations with Ostia Antica. DEATLANTIR II - HAR2017-89154-P - (Plan Nacional de I+D+i). Other funds have come from Andalusian Gouvernement (groups HUM-132, RNM-238 and RNM-293). It is a contribution to the Research Center in Historical, Cultural and Natural Heritage (CIPHCN) of the University of HuelvaThis work has been carried out through the project ´From the Atlantic to the Tyrrhenian. The hispanic ports and their commercial relations with Ostia Antica. DEATLANTIR II - HAR2017-89154-P - (Plan Nacional de I+D+i). Other funds have come from Andalusian Gouvernement (groups HUM-132, RNM-238 and RNM-293). It is a contribution to the Research Center in Historical, Cultural and Natural Heritage (CIPHCN) of the University of Huelva

A multidisciplinar analysis of sediments collected in diferent environments of the Doñana National Park (Guadalquivir estuary, SW Spain) provides an overview of the textural, mineralogical and physico-chemical parameters that control the distribution of benthic foraminiferal tests in this Biosphere Reserve. These microorganisms are absent in the fne quartzitic sands that constitute the substrate of temporary ponds with brief hydroperiods located in the dune systems and spits, as well as in other ponds with low conductivities or hypersaline conditions located in the inner marshlands or near the Guadalquivir river banks. Dead benthic foraminifera are mainly found on phyllosilicate-rich, silty-clayey substrates. The taphonomic analysis of the main species (Ammonia tepida, Haynesina germanica, Trochammina infata, Entzia macrescens) points to its deposit in situ. Cluster analysis permits to delimitate six foraminiferal assemblages. Cluster II (A. tepida+H. germanica) is the dominant assemblage in the central ponds and the margins of the main channels, while cluster IV (T. infata+E. macrescens) is restricted to some ponds located on the high marsh and cluster VI (Ammonia beccarii+Quinqueloculina spp.) is abundant on external beaches. Tidal fuxes cause the transport of these last marine benthic species and some plaktonic forms both to the inner areas of the estuary and to these beaches. info:eu-repo/semantics/publishedVersion

This paper investigates the paleoenvironmental evolution of a core extracted in the middle sector of the Tinto River estuary, SW Spain, one of the most polluted areas in the world due to mining over thousands of years (>4 kyr BP) and recent industrial discharges. This evolution includes alluvial sands (>6.4 cal kyr BP), bioclastic sands and silts deposited in subtidal and intertidal channels during and after the Holocene transgression maximum (6.4-4.3 cal kyr BP), the sedimentation of clayey-sandy silts in low and high marshes during the last 2.4 kyr BP and a final anthropic filling. Three sharp peaks of pollution have been detected, representing a) a natural origin during the Holocene transgression; b) the impact of the first mining activities (~4.5 cal kyr BP); and c) the effect of industrial discharge and a new period of mining activity throughout the 19th and 20th centuries. Foraminifera, ostracods and molluscs disappeared during these last two peaks., Este trabajo investiga la evolución paleoambiental inferida a partir del estudio de un testigo extraído en el sector medio del estuario del río Tinto (SO de España), una de las zonas más contaminadas del mundo por actividades mineras milenarias (>4 kyr BP) y descargas industriales recientes. Esta evolución incluye arenas aluviales (>6.4 cal kyr BP), arenas bioclásticas y limos depositados en canales submareales e intermareales durante y después del máximo transgresivo holoceno (6.4-4.3 cal kyr BP), la sedimentación de limos arcillosos-arenosos marismeños durante los últimos 2.4 kyr BP y un relleno antrópico final. Se han detectado tres picos de contaminación, que proceden de: a) un origen natural durante el máximo transgresivo holoceno; b) el impacto de las primeras actividades mineras (~ 4.5 kyr BP); y c) el efecto conjunto de los vertidos industriales y un nuevo período de actividad minera durante los siglos XIX y XX. Los foraminíferos, ostrácodos y moluscos desaparecieron durante estos dos últimos picos.

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Este trabajo describe la distribución de los ostrácodos en el sector central (cuenca de Malamocco) de la laguna de Venecia. Se identificaron más de un centenar de valvas y caparazones pertenecientes a 20 especies. Pueden diferenciarse 3 asociaciones de ostrápodos:(1) Asociación de Cyprideis torosa, bien presentada en el margen lagunar interno sometido a aportes de aguas dulces;(2) Asociación de Xestoleberis communis, presente en medios con escaso gradiente energético; y (3) Asociación de Pontocythere elongata, formada por especies marinas introducidas en el flujo mareal en el área próxima a la entrada al Puerto de Malamocco. No se han encontrado ostrácodos en medios de la escasa renovación de las aguas, fuerte hidrodinámica o bajos niveles de algas y otros alimentos de estos microorganismos.

The elemental content&mdash, mainly trace elements&mdash, of samples from two boreholes (PLN, CM) with evidence of tsunamiites, located in the Do&ntilde, ana National Park (SW Spain), were studied. The geochemical variations of the REE, LILE, HFSE, and other elements (Al, Ti, S, Na, Br, Sc, Co, Cr) were interpreted according to the mineralogy present in the samples. The results obtained show the geochemical complexity of the estuarine paleoenvironments, in this case with the existence of three Holocene-age tsunamigenic deposits (around 4.25, 3.56 and 2.2&ndash, 2 kyr BP). The statistical analysis of the samples&rsquo, geochemistry, by means of linear correlation and factor analysis, made it possible to differentiate two associations. The first is representative of an inherited mineralogy (REE-Y-Rb-Sr-Cs-Th-U-Hf-Al-Ti-Co-Cr-Sc), the second includes elements (Br-Na) linked to mineral formation under evaporite conditions (halite). The trace element geochemistry of sediments thus becomes an excellent tool to identify tsunamiites in the studied zone, especially those elements that are clear proxies for marine incursions (Na, Br, Sr) and high energy events (Hf, Ti). The parent area of the provenance of the materials is mainly of felsic composition.

On August 3, 1492, Christopher Columbus departed from the port of Palos de la Frontera, located in a small cove in southwestern Spain, and returned to this same port on March 15, 1493. On the basis of sedimentology, geochemistry, paleontology and dating of a long core (18 m) collected in this cove, thirteen facies are distinguished in the Neogene-Holocene evolution of its sedimentary infilling, with a transition from Miocene marine environments to Late Holocene marshes, going through an intermediate period that includes fluvial gravels, alluvial sediments and shallow coastal deposits that characterize the maximum of the Fladrian transgression in this area (~6.5 cal kyr BP). These data and others contributed by historical sources allow an approximate reconstruction of this cove at the end of the 15th century.

In recent decades, numerous studies have focused on the paleoenvironmental reconstruction of coastal areas, with special emphasis on the detection of tsunami layers. These multidisciplinary investigations usually do not study the mineralogy of the environment as well as the underlying or overlying layers.This paper analyzes the whole-rock mineralogy and clay minerals contained in seven short cores obtained in the Donana National Park (SW Spain) and deposited during the 5.000–1.500 cal. yr BP interval.The main purpose is to deduce the paleoenvironments from which the sedimentary facies present in them were formed and an approximation to the transport mechanisms involved in their formation. Results of X-ray diffraction analysis indicate that the main minerals are phyllosilicates, quartz and calcite, with smectites and illite being the most abundant phyllosilicates. According to the whole-rock mineralogy and additional statistical procedures (correlation, cluster analysis), the main source of quartz is the erosion of Donana spit, while the Guadalquivir river, its tributaries and the old lagoon have contributed mainly with smectite-rich phyllosilicates. On the contrary, waves, tides and high-energy events introduced illite and bioclasts in an old lagoon from the nearby shallow marine sectors. Consequently, the mineralogical analysis is revealed as an interesting tool for palaeoenvironmental reconstruction in this area, since it varies between different sedimentary environments. In addition, the combined study of whole-rock and clay mineralogy detects the tsunami layers and the provenance of their sediments in the studied cores.

A lacustrine carbonate facies has been investigated in Middle Miocene successions of the western side of the Moura-Marmelar basin, Southern Portugal in order to evaluate paleoenvironments in which carbonates formed, by using geochemistry and mineralogy. The studied formation corresponds to a recent unearthed section of a calcrete with an homogeneous carbonate facies comprising fine, whitish, and powdery material, and the only detected difference is a slightly hardness decrease towards the top, as well as an increase of weathered rock fragments (schist). The calcrete is calcium rich, even some magnesium enrichment was observed at the middle level, which is differentiated by a general depletion of all chemical elements, particularly REE, in both the bulk and clay-size fraction. Regarding the mineralogy, calcite prevails, and dolomite is only present in the middle level of the calcrete, together with a smectite enrichment, suggesting changes to more alkaline and low drainage, lacustrine and arid to semi-arid conditions.

The major changes that occurred in the southwestern estuaries of the Spanish Atlantic coast during the last 6500 yr BP were simultaneous to human settlement and therefore the understanding of their coastal evolution will help interpreting human patterns in these areas. The study of the morpho-sedimentary features of new outcrops appearing in the middle sector of Saltés Island (Huelva Estuary, Spain) has been used to develop a model to understand the complex evolution of sand barriers than can be applied to similar inlets along the Atlantic Iberian coast. The first human settlements (6000–4000 yr BP) in the early Huelva Estuary (Tinto and Odiel rivers) were located in the ancient coastal banks or in the nearby hills. From 4000 yr BP onwards, the estuarine sediments started to emerge as sand barriers and chenier plains, prograding towards the mouth. As the littoral strands stabilized morphologically, they were colonized by human settlements in successive periods, the oldest inland (Almendral) and more recent outward (Cascajera). The study of the upper sedimentary layers of La Cascajera barrier display a tempestitic sequence of landward progradational washover-fans. The calibrated and modelled AMS dates in marine shells provide a storminess time range between the second half of first century BCE and the entire first century CE. Sedimentary records are useful to evaluate environmental changes, either from natural or anthropogenic causes, such as global and climate change. The interrelationship between the archaeological findings (mainly salting fish factories and old ports) and the morpho sedimentary evolution at the mouth of the Tinto and Odiel rivers allows us to highlight not only the Huelva Estuary's dynamics evolution, but also the possible regional patterns of human habitation from the beginning of the present sea-level highstand (middle Holocene). Ministerio de Economía y Competitividad CGL2010-15810/BTE European Union (UE) EU Excellence Project of the Andalusia Board SEJ-4770

The analysis of shell deposits eroded by a ebb-tide channel on Saltes Island (Tinto-Odiel estuary, SW Spain) resulted in the identification of a new shell midden, associated with the activity of a nearby Roman factory over the 4th-5th centuries CE. This midden differs from other old shell deposits (sandy tidal flats, cheniers, washover fans) in several features: a) its malacological content, dominated by edible species (mainly the bivalve Glycymeris nummaria) and differentiated by statistical analysis; b) a partial selection and better conservation of Glycymeris nummaria (Linnaeus), its most abundant species; c) the absence of microfauna, which implies a previous washing to its final deposit; and d) an age concordant with the one deduced from the Roman amphoraic remains found in this area and subsequent to the washover fans on whom it was deposited. All these features, together with the absence of both anthropic fractures or cooking, would indicate that this Roman shell midden was the end result of a trawling on subtidal Glycymeris-rich sandy bottoms with adjacent grasslands, where the gastropod Bittium reticulatum (da Costa) was the most abundant mollusc. This gastropod is the dominant species in the remaining shell deposits.

Estuaries are very sensitive ecosystems to human activities and the natural evolution of their drainage basins located upstream. Pollution derived from human activities, such as historical mining or recent industrial wastes, can significantly affect their environmental quality. This paper analyzes the silver and copper contents of four cores extracted in two estuaries of SW Spain. Its chronology and vertical evolution allow to differentiate the effects of several pollution episodes (natural, Roman, 19th-20th centuries) on its different sedimentary environments in the last 6 million years. Possible future applications are included in the fields of environmental management or even education.

Virtual fieldtrips in palaeontology and geology offer an expanded environment to make field sites more accessible for a broader audience. Based on extensive experience working in upper Neogene deposits in the province of Huelva, on the western edge of the Guadalquivir Basin, we have selected 10 sites for their regional palaeontological-geological interest (geosites). By applying geoinformatic tools, we have produced a virtual 3D tour of the georeferenced geosites, integrating multiple thematic digital layers (including geological maps, topographical maps, a digital terrain model and orthophotos). Each stop in the tour contains descriptive and graphic elements that can be viewed in free virtual globes (e.g., Google Earth), combined with diagrams, photographs and information sheets that quantitatively assess the cultural tourism, scientific and educational value of the geosite. From this digital 3D geodatabase, we propose a virtual flight itinerary that can be displayed in compatible video formats and using new technologies, such as smartphones, tablets or iPads.

During the late Neogene, the Mediterranean Sea was connected with the Atlantic Ocean by two straits: the northern Betic Strait and the southern Rifian Strait. In this paper, we analyze the main palaeoenviromental changes produced in the western sector of the Betic Strait during the late Tortonian–middle Messinian (7.4–6 Ma). The temporal evolution and statistical analysis of benthic foraminiferal assemblages both in cores and surface sections of the western Guadalquivir Basin (SW Spain) allow drawing an initial important deepening from the late Tortonian calcarenite coastal areas to the well oxygenated, upper slope palaeoenvironments of the latest Tortonian to early Messinian, with a latest Tortonian condensed horizon composed by glauconitic silts deposited in the middle-outer shelf. The lower Messinian silts and clays (7.2–6.3 Ma) were deposited in a upper slope scenario, with a small oxygen depletion at 6.48 Ma. The 6.3–6.2 Ma interval was characterized by an important sea level drop and the presence of low oxygenated, outer shelf palaeoenvironments in this area, coinciding with a global glaciation. Prior to the Messinian Salinity Crisis (5.97–5.33 Ma), the upper slope palaeoenvironments were initially re-established (∼6.2–6.1 Ma) and finally a new regressive period (∼6 Ma) preceded Messinian Salinity Crisis.

This paper analyzes evidences of predation observed in ostracod populations collected in the southwestern Spanish shelf (0–70 m depth). Examination of seventy-two samples and almost 17,300 specimens allowed recovering more than 135 bored valves and carapaces. Percentages of bored specimens are very low (< 2%), with the highest values in isolated samples with low to very low ostracod densities. Two main types of boreholes can be distinguished: a) Oichnus paraboloides Bromley, accounting for over 70% of the total boreholes; and b) Oichnus simplex Bromley. Boreholes are concentrated mainly in the central and dorsal areas of the valves. Borehole diameter shows a positive but not significant correlation with the sizes of the predated valves. This diameter is usually higher in shallow marine areas. Predation affects the most abundant species of this shallow marine environment (mainly adults and the last juvenile instars). Ornamentation seems to be secondary in the predatory strategy.

On the basis of mineralogy, chemical and palaeontological data collected in a long core (93 m) three associations of facies are distinguished in the Late Pleistocene–Late Holocene evolution of the sedimentary infilling in nowadays Donana National Park. From the lower, middle and upper associations of facies three sedimentological phases have been established. In the oldest phase (> 44 kyr BP), this area was occupied by supratidal, freshwater marshes located close to a brackish lagoon and inundated suddenly by brackish-marine inputs. The following phase (44–7 kyr BP) is characterized by the transition from supratidal to intertidal conditions, with the alternation of freshwater or brackish marshes situated very close or in the margin of the former lagoon and submitted to episodes of desiccation or tidal inundation. The last phase (7–3.0 cal kyr BP) comprised: a) a marine inundation during the maximum of the Flandrian transgression (∼ 7–6.5 cal kyr BP); and b) the progressive infilling of a brackish lagoon with marine connection and permanent fresh water inputs (6.5–3.5 cal kyr BP), partially enclosed by the Donana spit. The phyllosilicate-rich, clayey–silty sequence of this latter infilling is interrupted by tsunami-like deposits at 4.2–3.6 cal kyr BP and 3.6–3.0 cal kyr BP. These high-energy events are characterized by textural (bimodal grain-size distribution, sorting decrease), mineralogical (crystallochemical changes in illites, increasing dolomite content) and geochemical changes (Ti anomaly), besides a sudden introduction of marine bivalves and microfauna and a strong decrease or the almost disappearance of the brackish ostracode assemblage. Ages of these deposits coincide with those indicated for other tsunamigenic layers detected in the southwestern Spanish coasts and some deep cores collected near the African–European plate boundary.

This review analyses the ostracod record in Holocene tsunami deposits, using an overview of the 2004 Indian Ocean tsunami impact on its recent populations and the associated tsunamigenic deposits, together with results from numerous investigations of other Holocene sequences. Different features such as the variability of the local assemblages, population density, species diversity, age population structure (e.g., percentages of adults and juvenile stages) or taphonomical signatures suggest that these microorganisms may be included amongst the most promising tracers of these high-energy events in marshes, lakes, lagoons or shallow marine areas.

This paper analyzes the lithostratigraphic features and ostracod associations of the Pliocene deposits located in the western sector of the Guadalquivir basin (SW Spain). A regressive cycle is defined by the vertical distribution of five main facies (FA-1 to FA-5), which were deposited in upper bathyal to fluvial palaeoenvironments. The broad palaeontological record is utilized to draw a general outline of the food chain in each palaeoenvironment. A comparison with the Pliocene ostracod distribution of southeastern Spain, southwestern France and Portugal permits to define a common ostracod biozonation for southwestern Europe during this period. Four main marine biozones are distinguished: (a): Pontocythere elongata biozone (infralittoral); (b): Costa edwardsii biozone (shallow circalittoral); (c): Bosquetina carinella biozone (deep circalittoral); and (d): Henryhowella asperrima biozone (upper bathyal). Freshwater, brackish and lower bathyal/abyssal species are very scarce in this area during this period.

In this paper, we analyze two short cores collected in the Tinto estuary (SW Spain), and describe the palaeoenvironmental evolution of this area during the last two millennia, along with the influence of historical mining activities and recent industrial pollution on sediments and microfauna (foraminifera and ostracoda). Although there were no significant changes in the distribution of microorganisms, a first pollution period (0-150 AD) was recorded in high sediment pollution by Cu in the shallow palaeochannels of the middle estuary. During this period and the following 1700 years, tolerant pioneer species of both foraminifera and ostracoda were found predominantly in the inner, protected areas of the estuary, while the bottom sediments were subjected to high hydrodynamic gradients, and consequently showed lower density and diversity of organisms. In the last 150 years, acid mine drainage processes, introduction of a new mining period, and the polluted inputs derived from two industrial processes resulted in increased heavy metal contamination of the bottom sediments, and corresponding extirpation of ostracodes and restriction of foraminifers to the inner zones of the estuary.

The application of the Poisson regression to the populations of the benthic foraminifer Ammonia tepida collected in three south-western Spanish estuaries permits to obtain a quantitative approach between some environmental variables and the number of individuals of this species. Although the three general models are unsatisfactory to predict the observed abundance of this micro-organism, a partial statistical analysis permits to detect quantitatively the impact of each variable. This analysis indicates an increasing abundance from the high-salt marshes to the subtidal channels and higher densities in those samples subjected to very euryhaline conditions. Increasing sand percentages show negative effects on the A. tepida abundance, whereas the silt contents do not affect significantly to this species and increasing organic carbon percentages have a small positive effect on the A. tepida densities.

Integrated analysis of a 50-m long sedimentary core collected in the central part of the Odiel estuary (SW Atlantic coast of Spain) allows delineation of the main paleoenvironmental changes that occurred in this area during the Holocene. Eight sedimentary facies were deposited in the last ca . 9000 years BP, confirming a transgressive–regressive cycle that involves the transition from fluvial to salt marsh deposits with intermediate marine tidal deposits. A storm event is detected at ca . 5705 14 C years BP (mean calibrated age) with distinct lithostratigraphical, textural, geochemical, and palaeontological features.

A multivariate analysis of the foraminifera collected in three estuaries of southwestern Spain (Guadiana, Piedras, Tinto-Odiel) permits recognition of three main assemblages, with spatial distribution depending on sedimentary environments, grain size classes and salinity variations. Assemblage 1 (Trochammina inflata, Jadammina macrescens) is typical of salt marsh deposits with high salinity variations and percentages of important silt. Assemblage 2 (Ammonia beccarii, Ammonia tepida, Astrononion stelligerum, Elphidium williamsoni) includes the most abundant estuarine species, with increasing densities from the channel margin to the subtidal channel. Assemblage 3 (Quinqueloculina seminulum, Elphidium crispum) is mainly found in the sandy sediments of the subtidal channels located near the mouth, with normal marine conditions. These results and the sedimentological interpretation of seven drill cores collected in the Domingo Rubio Channel (Tinto River) allow reconstruction of the palaeogeographic changes of this small estuary in the last ca. 6500 14 C years BP. Seven phases were distinguished, with an evolution from an open marine bay to

Ostracods are microcrustaceans that grow by moulting (eight to nine instars in most cases) and, consequently, studies of its populations need the application of some special techniques. The population age structure techniques [Whatley, in: Ostracoda in the Earth Sciences, 1988, pp. 245–256] are a simple statistical method to estimate paleoenvironmental conditions in fossil/Recent populations of ostracods. For its application, it is necessary to determine the percentages of each instar present in the samples studied, in order to analyze the different types of population age structure histograms and their (paleo-)environmental interpretations. Some potential applications are the (paleo-)energy levels or the sedimentation rates. In this paper, these special techniques are applied to Recent populations of the ostracod Pontocythere elongata collected in littoral sediments of southwestern Spain. In this area, the relative percentages of this species and the adult percentages are closely related with depth and consequently this species was used as a bathymetrical tracer in shallow Neogene areas of the Guadalquivir Basin. In addition, a first three-step multivariate analysis permits the definition of three groups, closely related to the theoretical models proposed by Whatley: (a) Group 1 structure or biocoenosis, present either in Recent low- to medium-energy environments located in erosional coastal stretches and Neogene fair-weather conditions; (b) Group 2 structure or high-energy thanatocoenosis, observed either in Recent river mouths with groynes and Neogene storm and post-storm conditions; and (c) Group 3 structure or low-energy thanatocoenosis, characteristic of Recent, progradational coastal areas and present in the Recent–Neogene deeper areas analyzed in this paper (30–40 m depth). This separation is mainly controlled by intrinsic factors (i.e. the natural growth of this species), whereas the extrinsic factors (i.e. the hydrodynamic levels) are only a minor cause of the distribution of this species in the area studied.

Resumen Se realiza el estudio sistematico de los ejemplares pertenecientes al genero Heterostegina de diversos niveles lumaquelicos en sedimentos de la unidad arenosa basal de la serie neogena en el sector occidental de la Cuenca del Guadalquivir (SO de Espana). La determinacion especifica de estos ejemplares ha llevado a una revision y correccion de la especie Heterostegina gomez-angulensis Perconig . Se describe y figura por vez primera la generacion microesferica de esta especie, se realiza una redescripcion de las formas megaloesfericas que permite la distincion de dos morfotipos diferenciados, y se evalua su interes cronoestratigrafico.

One hundred and twenty-one samples were collected in three estuaries of the Huelva littoral (SW Spain). The 12,923 individuals picked were assigned to forty-seven species. The analysis of the foraminiferal percentages allows the distinction of seven assemblages: two salt marsh assemblages ( Trochammina inflata and Jadammina macrescens ), four assemblages widely represented both in the channel margins and the channels ( Ammonia inflata, Astrononion stelligerum, Cribroelphidium vadescens, Ammonia ammoniformis ) and one marginal marine assemblage ( Ammonia beccarii-Quinqueloculina spp). The distribution of these assemblages is controlled by the salinity, the altitude above the lowest tidal level and, to a lesser extent, by the grain size, organic matter and the test transport. In the Tinto-Odiel estuary, both effects of heavy metal pollution and sedimentary changes in the foraminiferal distribution were analyzed, indicating some recuperation mainly in the Odiel river, one of the most polluted areas of the world.

The distribution and abundance of both living and total ostracod populations from the estuaries of the southwestern Spanish coast are discussed. A total of 68 species were obtained from 120 bottom samples collected in the channels, channel margins and salt marshes. Four assemblages were recognized in this area: (a) Urocythereis oblonga assemblage, with marine species well-represented in sandy substrates located near the mouths; (b) Loxoconcha rhomboidea assemblage, mainly developed in the quiet tidal channels conected with the main channels of the marine domains; (c) Loxoconcha elliptica assemblage, enclosing the most cosmopolitan and euryhaline species, very abundant in muddy sediments and low to moderate hydrodynamic conditions; and (d) Leptocythere porcellanea assemblage, only observed in the clayey-silty channel margins of the most protected ebb channels. In these transitional environments, very unfavorable conditions for the ostracod development were found in: (a) the erosional channels and channel margins; (b) most of the salt marsh samples with high subaerial exposure; and (c) sectors with high metallic pollution levels and acidic waters.

In the Venice lagoon, ostracods from 99 recent samples were studied. The biocoenosis is more abundant in the inner margin, near some little channels. The microfaunal analysis delimited three estuarine associations, with numerous valves of Cyprideis torosa, and one marine association (Pontocythere turbida). Salinity, hydrodynamics, nutrients and substrate are the main factors which control the distribution of these microorganisms. This distribution is very similar in other recent lagoons of Italy.

Six estuarine facies were distinguished recording the Holocene history of sea level rise relating according to the start and development of the Holocene transgression which flooded the coast of Huelva: Facies 2 (gravels), Facies 3 (grey clayey silts), Facies 5 (well sorted sands), Facies 4 (silty sands), Facies 5 (black clayey silts), and Facies 6 (red muds). This group overlies Neogene sediments (Facies 1). Three faunal assemblages (Open bay (OB), Central estuary (CE), and Wave domination (WD)) including remains of macrofauna, foraminifers and ostracods plus depositional features, are identified in a sedimentological log constructed from a borehole with a continuous core, sunk in the central basin of the Odiel River estuary, Huela coast, SW. Spain. The OB assemblage requires shallow and protected zones controlled by low energy tidal currents; the CE assemblage is located within an intertidal zone, where reworked marine forms of foraminifers, ostracods and scattered macrofauna co-exist with small estuarine foraminifers and ostracods; the WD assemblage comprises tests of marine macrofauna with fractured shells plus large marine foraminifers and estuarine ostracods. During the first stage of continuous sea level rise (8720±260 BP to 5390±155 BP), estuarine accretion, high energy tidal currents and wave action took place successively, allowing the development of the OB, CE and WD assemblages. The second stage (5390±155 BP to Present), with a stabilized sea level, comprised a vertical decrease of energy, with tidal currents favouring deposition in shallow tidal channels and marsh zones, leading to less energetic CE assemblages within the estuarine central basin. High sediment supply resulted in deposition during this stage, which shows a regressive nature.

The Holocene filling of the Tinto-Odiel Estuary comprises seven lithofacies over a Mio-Pliocene substrate. The sequence includes three system tracts: lowstand system (10 000 to 8700 years BP), transgressive system (8700 to 7000 years BP), and regressive system (7000 to Recent). Twenty sediment samples from the 50-m borehole were analyzed for their major components and minor element concentrations. Two multivariate analysis methods, principal component analysis and cluster analysis, were performed in the analytical data set to help visualize the sample clusters and the element associations. Samples corresponding to unpolluted, pre-mining sediments are clearly separated by cluster analysis, mainly as a result of the low content in sulphide-associated heavy metals such as Cu, Zn, As, Ag, and Pb. So, these sediments may be utilized as a background for geochemical analysis (bulk sample) in other adjacent estuaries, both in sandy and silty-clayey sediments. As a consequence of large-scale mining and smelting operations occurred since prehistoric times on the river banks, a rapid rise in the metal pollution was found in the upper 2.5 m of the natural filling, with values exceeding up to ten times the natural background levels. In addition, since the mid-1960s, large amounts of waste and pollutant effluents have been discharged from industries located around the estuary, increasing the heavy metal content in the last 0.3 m of the natural sedimentation.

By studying the ostracod assemblages in the Huelva Estuary, the impact of natural and human factors on the populations of these organisms can be determined. Three periods were defined in 12 cores collected along the estuary: (1) pre-industrial period (before 1966), with moderate pollution in some estuarine sectors because of prehistoric mining; (2) industrial period (1966–1985), with pollution increasing by wastes derived from industrial processes; and (3) post-industrial period (1991). No ostracods and live macrofauna were found in environments with extreme subaerial exposure (fluvial bars, meanders and salt marshes), even in pre-industrial sediments. During this period, the ostracod distribution was controled by the salinity tolerance in the main channel of the Odiel River, the euryhaline species being replaced by marine forms toward the estuary mouth. Acidic industrial wastes causes the disappearance of ostracod assemblages (mainly Loxoconcha elliptica ) in this environment and the channel border. Fillings of some distributary channels have greatly affected the ostracod and macrofaunal assemblages in these zones, with a dramatic drop in the diversity and number of individuals. In April 1991, live ostracods were exclusively found in the Punta Umbria subsystem, a relatively protected environment because distance and salt-marsh barriers protect it from industrial effluents.