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La Pastora tholos is the most complete and characteristic megalithic monument of the Valencina de la Concepción-Castilleja de Guzmán mega-site. This monument was built using three types of rock, each with different functions and coming from three different places: Paleozoic quartzarenite, granite, and Tertiary calcareous sandstone. A detailed petrological study of the rocks of the tholos and outcrops of similar rocks in the surroundings has been carried out, locating the possible source areas in areas at least 30 km to the N of the monument for the quartzarenite, 15 km for the granite, and 15 km to the S for the sandstone. Therefore, the community that built the monument has a high knowledge of the nature by, which allows them to locate these resources, and a sufficient social organization to exploit them and move them to the mega-site. In this sense, the layout of the outcrops suggests the possible use of boats or rafts to facilitate their displacement, or at least part of their movement. [ABSTRACT FROM AUTHOR]

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]

Valencina (Seville, Spain) is one of the most important megalithic sites of the third millennium BCE in Western Europe. Among its most celebrated monuments are the tholoi of Montelirio, La Pastora, Matarrubilla, and Structure 10.042-10.049. Although sharing the same architectural tradition, these monuments were raised at different times of Valencina's history and present important formal differences. In particular, the tholoi of La Pastora and Matarrubilla contrast with that of Montelirio in that they are devoid of artistic ornamentation such as paintings and engravings, showing instead an inordinate number of natural geological features. This study, focusing on La Pastora and Matarrubilla, offers an innovative approach to the notion of "megalithic art." Firstly, these elements are characterized and classified and their natural origin established. Thus, the calcareous sandstone blocks dated from the Tertiary reveal structures on their surfaces generated by biological (bioturbation) and physical (by currents) processes during the Neogene. The surfaces of certain slabs of identical lithology at La Pastora experienced more recent intense marine bioerosion and bioconstructions in the form of Ostrea preserved to this date. Secondly, we emphasize the choice of different rock types following a certain pattern or serving to highlight a particular constructive element. In sum, all the natural elements bear highly aesthetic qualities and appear to have been deliberately chosen to highlight specific decorative or symbolic aspects. As a result, we suggest that future research on "megalithic art" should include analogous geological examinations in order to discern the origin and nature of the different elements. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The malacological analysis of the Cañada Honda shell midden (Tinto-Odiel estuary, SW Spain) has allowed an approximation of the palaeo biodiversity of this sector during the Mesolithic. During this period, the progressive marine transgression caused the flooding of this estuary, coinciding with an initial intensive capture of the bivalves Lutraria and Ruditapes decussatus in the northern and southern sector of this site, respectively. In a second phase, Ruditapes decussatus was the main collected species in all sectors. This last period coincided with some diversification in catches, still dominated by Ruditapes decussatus but with significant proportions of Cerastoderma edule. This stage witnessed a progressive sedimentary filling of the estuary and the creation of marshes and barrier islands. The almost total fragmentation of the specimens would imply that the surface of this shell midden was exposed for a long time while in use. In addition, an occasional charring of some molluscs has been detected. The main molluscs of this site are also the most abundant in other later shell middens (∼cal 5.2–4 kyr BP), indicating an important perpetuation of the collecting and/or eating habits in this environment. All the species determined in them are also currently found in this estuary and its surroundings, where they are also captured. [ABSTRACT FROM AUTHOR]

• The Holocene paleoenvironmental evolution of a coastal lagoon is recorded. • An open bay was progressively confined until forming a restricted lagoon. • The 1755 tsunami deposits are identified near the top of the succession. • This deposit constitutes the first faunal evidence of this event for the Mediterranean Sea. 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. [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]

This paper studies the Late Holocene benthic foraminifera from a continuous core extracted in the Doñana National Park (SW Spain). In this core, the foraminiferal assemblages confirm the Late Holocene lagoon (historically so-called Lacus Ligustinus) during the Roman period, about 2000 years ago. The more open, deepest areas of this lagoon were dominated by Ammonia tepida and Elphidium spp., while Haynesina germanica was the most representative species of the shallow, more restricted zones. The vertical variations of these assemblages, together with associated sedimentological and macrofaunal changes, allow recognizing three high-energy events (HEE) between 500 BCE and 500 CE, which also left an extensive sedimentary record in nearby coastal areas: two tsunamis (HEE-1 and HEE-3) and a storminess period (HEE-2). [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]

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]

Abstract: 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 14C years BP (mean calibrated age) with distinct lithostratigraphical, textural, geochemical, and palaeontological features. [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]

The elemental content—mainly trace elements—of samples from two boreholes (PLN, CM) with evidence of tsunamiites, located in the Doñana 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 2.2–2 kyr BP). The statistical analysis of the samples' 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. [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]

A Late Pleistocene surface full of tracks and trackways (named 'Matalascañas Trampled Surface') has been exposed at the base of the 'El Asperillo' cliff (Doñana National Park, Matalascañas, Huelva, southwestern Spain) as a result of recent storms. This surface has been identified as the bottom of the unit AU1, according to the local stratigraphic section, and originated during the marine stage MIS-5 (∼106 ± 19 kyr). This trampled surface records exceptional tracks and trackways of different terrestrial vertebrates. In particular, three morphotypes of tracks ascribed to Artiodactyla (the auroch Bos primigenius ? the red deer Cervus elaphus and wild boar Sus scrofa), one to Elephantidae (Palaeoloxodon antiquus), one of Canidae (Canis lupus), and three to waterbirds (geese, Anserinae, and waders, Charadrii) have been identified. This ichnoassociation is characteristic of a shorebird ichnofacies. We interpret this trampled surface to have been related to puddled areas of shallow waters in an inter-dune position, similar to present day examples in the Doñana National Park. • The Late Pleistocene aeolian deposits on Matalascañas (SW Spain) contain abundant mammal and bird tracks and trackways. • These deposits form a lower set of cliff-foot dunes and another of rampant sands. • The fossil tracks and trackways are concentrated in two units dated by OSL in 106 ± 19 kyr (MIS 5). • The tracemakers identified are artiodactils, elephants, wolves, waterbirds and shorebirds. • The palaeoenvironmental interpretation of the surface is related to puddled areas of shallow waters in an interdune position. [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]