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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.

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).

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.

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.

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.

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

Evidence of the AD 1755 tsunami consisting of the same type of accretions produced by the re-deposition of earlier sediments, has been recorded at three different height along the coast of Gibraltar: Along a shallow sandy shore, the tsunami wave reached a run-up of 2–3 m, whereas along steep, cliff–lined shores (Rosia Bay) it surpassed 5 m. An overwash deposit was also identified at the bottom of a lagoon (The Inundation), at 0.5 m b.s.l., on the isthmus that joins the Rock with the mainland. Southern submerged platforms (Vladi’s Reef) were also affected by the erosional backwash to a depth of 22 m. The tsunamigenic sediments exhibit a bimodal granulometry, mainly composed of sands with a coarser fraction composed of marine faunal shells remains, together with larger clasts derived from the rocky substrate. All remobilized sediments were dated by historical methods and radiocarbon dating. Se han registrado evidencias del tsunami de 1755 localizadas a tres alturas diferentes a lo largo de la costa de Gibraltar, todas ellas como resultado del mismo tipo de acreción producida por el re-depósito de sedimentos previos. A lo largo de las costas bajas y arenosas estudiadas, la ola del tsunami alcanzó una altura de 2 a 3 m, mientras que en litorales acantilados y con fuertes pendientes sobrepasó los 5 m. Se ha identificado un posible registro sedimentario en el fondo de una laguna costera (Inundation), a 0.5 m b.n.m., en el istmo que une la Roca con el continente. Por otro lado, las plataformas sumergidas, como la meridional de Vladi’s Reef, sufrieron erosión por la retirada de las olas a una profundidad de hasta 22 m. Los sedimentos tsunamigénicos poseen una granulometría bimodal, compuesta principalmente de arenas con una fracción más gruesa de restos de conchas marinas, junto con cantos mayores de rocas provenientes del sustrato. Todos los sedimentos removilizados por el tsunami han sido datados por métodos históricos y de radiocarbono. Research supported by the Spanish-FEDER Project CGL2010-15810/BTE, AHRC Research Grants (AH/E009409/1), and COST-action TD0902 SPLASHCOS (Submerged Prehistoric Archeology and Landscapes of the Continental Shelf). We thank reviewers and guest-editors for helpful comments. It is a contribution to IGCPs 526 (Risks, resources, and record of the past on the continental shelf), 567 (Earthquake Archaeology and Palaeoseismology), and 588 (Preparing for coastal change).

Ostracods from the Moguer section (Huelva province, SO Guadalquivir Basin) are here studied. 49 speces belong to 26 genera are described. The comparation with biostratigraphical studies executed in this materials and Atlantic and Mediterranean biozonations allow us to atribute a Lower Pliocene age (Tabianian) to this section. The analysis of available bathymetric data supports the view that the habitat of the Pliocene associations was shalow, near-shore with temperature over 16° C and salinities between 38-39‰.

This paper revises the response of freshwater ostracods to different environmental conditions and anthropogenic impacts, with a worldwide overview of the potential use of these microcrustaceans as bioindicators and several examples of applications in different scenarios. The development of either a single species or an ostracod assemblage is influenced by physical-chemical properties of waters (salinity, temperature, pH, dissolved oxygen), hydraulic conditions, bottom grain sizes or sedimentation rates. In addition to population and community changes, morphological and geochemical changes can also be detected in the ostracod carapace, which serves as a tracer of the water quality. All these features permit to delimit the spatial effects of urban sewages, mining effluents, agri- cultural wastes, watershed deforestation or road building. These data are the basis for the palaeoenvironmental reconstruction of cores, with an interesting application to archaeology. In addition, favourable results of recently developed bioassays, coupled with an important variability of local assemblages under changing conditions in both waters and sediments, suggest that these microcrustaceans may included between the most promising sentinels groups in freshwater areas. These microcrustaceans show high sensitivity to pesticides, herbicides, heavy metal pollution and oil inputs.