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Estuaries are excellent environments for identifying pollution episodes that have affected river basins, as their sediments are the final destination of some of the pollutants. This paper studies the geochemical evolution of five elements (As, Co, Cu, Pb, Zn) in a core extracted from the middle estuary of the Tinto River (SW Spain). The results are based on facies interpretation, ICP atomic emission spectrometry analysis, the application of a regional background to obtain the geoaccumulation index and dating. The main objective of this communication is the detection of natural or anthropogenic pollution episodes in the middle estuary of the Tinto River (SW Spain). Four pollution episodes have been detected: (1) ~5.8 cal. kyr BP, probably caused by natural acid rock drainage processes derived from the oxidation of the Iberian Pyritic Belt deposits found in its drainage basin; (2) 4.7–4.5 kyr BP, coming from the first mining activities and characterized by a significant increase in the concentrations of the five elements analyzed; (3) 1850–1960 interval, coinciding with intensive mining and characterized by increasing values of As and, to a lesser extent, Pb (intensive mining); and (4) the second half of the 20th century, with high element concentrations from mining and industrial effluents. All episodes show an increase in their geochemical classes deduced from the geoaccumulation index. This communication can serve as an example for assessing the impact of different types of pollution in estuarine environments. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The Roman port of Portus was the most important in the Mediterranean during the imperial period (27 BC–476 AD). It was made up of an outer port or Claudius basin and an inner hexagon or Trajan's port, joined by the Canale di Imbocco. The archaeobotanical record obtained in a continuos sediment core taken in this channel is made up of 19 types of plant macroremains, with a predominance of fibers of the seagrass Posidonia oceanica L., replaced by fluvial sediments in the upper part of the core. Seeds, fruits and thorns of aquatic species from marine or brackish waters, halophyte species, edible species, freshwater riparian vegetation and remains of charcoal and wood also appear regularly. According to the inferred palaeoenviromental evolution of this core, Portus was an area of fluvial-marine interaction during the Roman Empire, with brackish water conditions interrupted by stormy periods deduced from the record of P. oceanica. The archaeobotanical and sedimentary evolution points to a restriction of marine contributions and a final implantation of a fluvial environment. In this evolution, a specific interval with abundant charcoal and caryopses of Triticum could correspond to a fire, which was followed by a possible period of greater construction activity linked with large fragments of wood. • Fibers and Neptune balls of Posidonia oceanica dominated the filling of Portus. • The archaeobotanical record indicates an evolution from an initial marine domain to a final fluvial/anthropic phase. • High abundance of Neptune balls are tentatively correlated with stormy periods. • The joint presence of charcoal, caryopses of Triticum and larger wood fragments is associated with a fire. [ABSTRACT FROM AUTHOR]

Feral Pigeons have colonised all corners of the Earth, having developed a close association with humans and their activities. The wild ancestor of the Feral Pigeon, the Rock Dove, is a species of rocky habitats, nesting typically on cliff ledges and at the entrance to large caves. This habit would have brought them into close contact with cave-dwelling humans, a relationship usually linked to the development of dwellings in the Neolithic. We show that the association between humans and Rock Doves is an ancient one with its roots in the Palaeolithic and predates the arrival of modern humans into Europe. At Gorham's Cave, Gibraltar, the Neanderthals exploited Rock Doves for food for a period of over 40 thousand years, the earliest evidence dating to at least 67 thousand years ago. We show that the exploitation was not casual or sporadic, having found repeated evidence of the practice in different, widely spaced, temporal contexts within the cave. Our results point to hitherto unappreciated capacities of the Neanderthals to exploit birds as food resources on a regular basis. More so, they were practising it long before the arrival of modern humans and had therefore invented it independently. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The hypothesis that Neanderthals exploited birds for the use of their feathers or claws as personal ornaments in symbolic behaviour is revolutionary as it assigns unprecedented cognitive abilities to these hominins. This inference, however, is based on modest faunal samples and thus may not represent a regular or systematic behaviour. Here we address this issue by looking for evidence of such behaviour across a large temporal and geographical framework. Our analyses try to answer four main questions: 1) does a Neanderthal to raptor-corvid connection exist at a large scale, thus avoiding associations that might be regarded as local in space or time?; 2) did Middle (associated with Neanderthals) and Upper Palaeolithic (associated with modern humans) sites contain a greater range of these species than Late Pleistocene paleontological sites?; 3) is there a taphonomic association between Neanderthals and corvids-raptors at Middle Palaeolithic sites on Gibraltar, specifically Gorham's, Vanguard and Ibex Caves? and; 4) was the extraction of wing feathers a local phenomenon exclusive to the Neanderthals at these sites or was it a geographically wider phenomenon?. We compiled a database of 1699 Pleistocene Palearctic sites based on fossil bird sites. We also compiled a taphonomical database from the Middle Palaeolithic assemblages of Gibraltar. We establish a clear, previously unknown and widespread, association between Neanderthals, raptors and corvids. We show that the association involved the direct intervention of Neanderthals on the bones of these birds, which we interpret as evidence of extraction of large flight feathers. The large number of bones, the variety of species processed and the different temporal periods when the behaviour is observed, indicate that this was a systematic, geographically and temporally broad, activity that the Neanderthals undertook. Our results, providing clear evidence that Neanderthal cognitive capacities were comparable to those of Modern Humans, constitute a major advance in the study of human evolution. [ABSTRACT FROM AUTHOR]

Abstract: On the basis of mineralogy, chemical and palaeontological data collected in a long core (93m) three associations of facies are distinguished in the Late Pleistocene–Late Holocene evolution of the sedimentary infilling in nowadays Doñana National Park. From the lower, middle and upper associations of facies three sedimentological phases have been established. In the oldest phase (>44kyrBP), this area was occupied by supratidal, freshwater marshes located close to a brackish lagoon and inundated suddenly by brackish-marine inputs. The following phase (44–7kyrBP) 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 (7–3.0calkyrBP) comprised: a) a marine inundation during the maximum of the Flandrian transgression (∼7–6.5calkyrBP); and b) the progressive infilling of a brackish lagoon with marine connection and permanent fresh water inputs (6.5–3.5calkyrBP), partially enclosed by the Doñana spit. The phyllosilicate-rich, clayey–silty sequence of this latter infilling is interrupted by tsunami-like deposits at 4.2–3.6calkyrBP and 3.6–3.0calkyrBP. 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. [Copyright &y& Elsevier]

Abstract: Four phases are distinguished in the Mid-Holocene evolution of the southwestern Doñana National Park (SW Spain), based on the multidisciplinary study of sediments in drill cores. In the oldest phase (>5500–5400 cal. years BP), a coastal, brackish lagoon occupied the central part of the study area, partly enclosed by the Doñana spit and limited by fluvial levees. An evolution from subtidal to intertidal conditions characterized the areas located close to the inner side of the Doñana spit during the same phase. The following phase (∼5400–5200 cal. years BP) is characterized by a high-energy event (tsunami?), which caused the breakthrough of the Doñana spit and the creation of new littoral strands in the inner areas. In the first period of the third phase (∼5200–4200 cal. years BP), estuarine infilling was probably the dominant process, with the accumulation of phyllosilicate-rich clays in the lagoon bed. This was followed by a renewed phase of instability (∼4200–4100 cal. years BP) indicated by the presence of fine storm-lain deposits and thicker, probably tsunami-induced shelly deposits. The last phase (∼4100–3700 cal. years BP) comprises: a) an infilling period, with a diminution of the marine influence; and b) two new high-energy events, which caused the erosion of the Doñana spit and the creation of new cheniers. In the last 7000 years, the comparison of these results with a revision of both geological and historical records has revealed the occurrence of twenty tsunamis (at least) during this period in Portugal and southern Spain. Evidences of these high-energy events are washover fans, bioclastic coarse-sized layers within salt marsh deposits or the presence of giant boulders and pebbles. The determination of the recurrence period is very difficult owing to the very scarce data, although our data and other authors do not discard a possible periodicity of 2000 years for a cycle of two events separated by 300–400 years. [Copyright &y& Elsevier]

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. Image 1 • On August 3, 1492, Christopher Columbus departed from a cove in SW Spain. • Its sedimentary record includes the transit from a Miocene shelf to alluvial sediments. • Two geochemical peaks are related to the Flandrian transgression and Roman mining. • In 1492, the progressive filling hindered navigability in this cove. [ABSTRACT FROM AUTHOR]

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 Doñana 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 Doñana 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. Unlabelled Image • The mineralogy is a powerful tool to reconstruct sedimentary sources. • In the Roman Lacus Ligustinus, phyllosilicates and smectites were supplied by the Guadalquivir River. • The mineralogy of the outer lagoonal area was controlled by the Doñana spit. • High-energy events caused the introduction of bioclastic quartz-rich sands. • Illite was introduced from the adjacent shelf to the innermost lagoonal zones. [ABSTRACT FROM AUTHOR]

The analysis of shell deposits eroded by a ebb-tide channel on Saltés 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. Image 1 • Multidisciplinary analyzes permit to distinguish shell middens from other shell deposits. • Percentages of edible species, taphonomy or shell size delimit shell middens. • Statistics permits to delimitate shell middens from cheniers, washover fans or tidal flats. • Autoecology of the species delimits the fishing spaces of a Roman factory and the fishing techniques used. • Age of shell midden is consistent with that of the nearby archaeological remains. [ABSTRACT FROM AUTHOR]