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Atmospheric concentrations of 18 polycyclic aromatic hydrocarbons (PAHs) were measured in a rural area in northern Spain. Both the gas phase and particulate fraction were determined to evaluate the types and abundance of PAHs taken up by vegetation and the historical record of PAH deposition in an ombrotrophic peatland over the last 300 years. The total atmospheric PAH concentration was ca. 2.5 ng m−3, a value that is slightly lower value than those found in other rural areas, consistent with those of remote areas (Pyrenees, Alps, and Caledonian Mountains), and much lower than those recorded in urban areas. The particulate fraction showed a greater content of high molecular weight PAHs, whereas the gas phase was enriched in low molecular weight homologues. The concentration of total PAHs in the gas phase was higher than that in the particulate fraction (ca. 80%) and similar to that found in other localities in remote areas. PAHs showed seasonal variability. In this regard, the highest concentrations in the gas phase occurred in winter and autumn, whereas in the particulate fraction they were found in winter and spring. Of note, the concentrations of PAHs increased in the particulate fraction during the years in which fires occurred. The PAH content in peat-forming plants in this area showed a similar distribution to that of the gas phase. The historical record of the depositional fluxes of PAHs in an ombrotrophic peatland in the study area, which was dated radiometrically, allowed to reconstruct the changes in pollutant content between 1775 and the present. In general, the PAHs detected were of pyrogenic origin (fossil fuels and wood combustion). The concentrations of these pollutants increased from uniform background levels at the turn of the second half of the 19th century, which were linked to industrial development, to maximum values during the first half of the 20th century until the beginning of the 21st century, when the extraction and combustion of coal was extensive close to the study area. In contrast, in the uppermost part of the record, PAH concentrations decreased. This reduction is attributed to the implementation of environmental policies, although the concentrations of these pollutants were still greater than during the preindustrial period. To gain a detailed understanding of the deposition and evolution of PAHs in the study area, here it is reported on a new method that integrates current atmospheric data on PAHs with information on their accumulation in plants and the historical peat record of a rural area in Spain. The methodology described herein could be applied to other scenarios in the context of PAH pollution. • The molecular ratios for the PAHs found in Las Conchas mire suggest a pyrogenic fingerprint. • Consistent concentrations of PAHs from atmospheric, living plants and peat record are found. • Particulate fraction showed a greater content of high molecular weight PAHs. • Gas phase was enriched in low molecular weight PAHs. [ABSTRACT FROM AUTHOR]

The lipid content of three cores from Lake Enol (Picos de Europa National Park, Asturias, Northern Spain) was studied. The n- alkane profiles indicated a major input from terrigenous plants [predominance of high molecular weight (HMW) alkanes] since ca. 1695 AD to the water body, although the uppermost cm revealed a predominance of organic matter (OM) derived from algae, as the most abundant alkane was C 17 . Three units revealing different environmental conditions were defined. Unit A (ca. 1695–1860 AD) in the lowermost parts of ENO13-10 (< 12 cm) and ENO13-15 (< 28 cm) was identified and was characterized by higher OM input and evidence of minimal degradation (high CPI values, predominance of HMW n- alkanoic acids and good correspondence between the predominant n- alkane and n- alkanoic acid chains). These findings could be linked to the Little Ice Age, when cold and humid conditions may have favored an increase in total organic carbon (TOC) and n -alkane and n -alkanoic acid content (greater terrigenous OM in-wash), and may have also reduced bacterial activity. In Unit B (ca. 1860–1980 AD) the lack of correspondence between the n -alkane and n -alkanoic acid profiles of ENO13-10 (12–4 cm) and ENO13-15 (28–8 cm) suggested a certain preferential microbial synthesis of long chain saturated fatty acids from primary OM and/or bacterial activity, coinciding with a decrease in OM input, which could be linked to the global warming that started in the second half of the 19th century. In ENO13-7 the low OM input (low TOC) was accompanied by some bacterial degradation (predominance of HMW n- alkanoic acids but with a bimodal distribution) in the lowermost 16–5 cm. Evidence of considerable phytoplankton productivity and microbial activity was especially significant in Unit C (ca. 1980–2013 AD) identified in the uppermost part of all three cores (5 cm in ENO13-7, 4 cm in ENO13-10 and 8 cm in ENO13-15), coinciding with higher concentrations of n- alkanes and n- alkanoic acids, which were considered to be linked to warmer and drier conditions, as well as to greater anthropogenic influence in modern times. Plant sterols, such as β-sitosterol, campesterol and stigmasterol, were significantly present in the cores. In addition, fecal stanols, such as 24-ethylcoprostanol from herbivores, were present, thereby indicating a continuous and significant pollution input derived from these animals since the 17th century, being more important in the last 20 years. [ABSTRACT FROM AUTHOR]

Here we reconstructed the evolution of the Mazarrón Basin during the Pleistocene and Holocene. In this regard, we studied 9 cores with the aim to: 1) define a chronological framework; 2) obtain data on the palaeoenvironment; and 3) establish the relationship with recent tectonics. A total of 158 samples were recovered for amino acid racemization (AAR) dating, 4 for radiocarbon dating (14C), and 332 for sedimentological and palaeontological determination, and 110 for determination of the mineralogical content. These approaches allowed us to elucidate the evolutionary phases of the palaeo-landscape of the Mazarrón Basin, a fault-controlled graben affected by diverse faults, mainly those of Las Moreras and Rella. The ages of the records and the facies correlation indicate that Las Moreras Fault controlled sedimentation during Marine Isotope Stage (MIS) 7, whereas the Rella Fault was strongly active during the Middle Holocene. During MIS7, a brackish lagoon developed in the western area, overlying alluvial fan deposits. Later, the area was uplifted, thereby becoming exposed to erosion. The activity of the Rella Fault allowed sedimentation in the western part of the Mazarrón Basin during the Middle Holocene, while in the Upper Holocene sedimentation occurred in the eastern part. The Holocene transgression was reflected in a temporarily floodable marsh in the hinterland, with changing salinity conditions, from brackish to euhaline waters. Along the sea front, the marine influence was evident but not dominant. Thus, the Mazarrón Basin during the Holocene was brackish to highly euhaline, with variable biological diversity linked to a narrow and probably discontinuous communication with the sea, with restricted circulation and long flushing times, which was reflected by the significant presence of halite. The record ended with recent alluvial/anthropic sediments. [ABSTRACT FROM AUTHOR]

Here, we sought to reconstruct the Pleistocene and Holocene evolution of Cartagena Bay. Therefore, 16 borehole cores were analysed with the following aims: (1) to define a chronological framework; (2) to obtain data on the palaeoenvironment; and (3) to establish the relationship with human activities, especially focused on the reconstruction of the Carthago Nova (also known as Qart Hadasht) conquest. A total of 147 samples were recovered for amino acid racemisation (AAR) dating; 32 for radiocarbon dating (14C); and 159 for sedimentological, palaeontological, and biomarker determination. These approaches allowed us to elucidate the evolutionary phases of the palaeolandscape in Cartagena. The simultaneous use of AAR and 14C dating allowed the discrimination of spurious ages and the establishment of a chronological scale. During the Marine Isotope Stages (MIS) 7 and 5, the sea level (SL) in Cartagena Bay was almost the same as today. An alluvial plain developed in the northern area, and a delta was formed by an ephemeral river. In contrast, during MIS4, after a fall in SL, a wide sandy coastal plain emerged, leading to the accumulation of colluvial and aeolian deposits. The Holocene transgression was reflected in the hinterland in a late and temporarily floodable marsh fed by alluvial fans and creeks, producing a salinity gradient from freshwater to brackish and saline waters. Along the sea front, the marine influence was evident but not dominant, grading up and landwards to saline and freshwater marshes. Therefore, at the time of Scipio's conquest, the geography of Carthago Nova was quite different from that described by Polybius. The Roman's sudden attack seized Qart Hadasht from the south-west, avoiding the marshy area and not crossing a fast and deep ebb stream as it never existed on the Mediterranean Iberian coast. [ABSTRACT FROM AUTHOR]

Objectives: To present a new dental specimen that will provide additional evidence for a better understanding of early European Upper Pleistocene hominin morphological variability. Materials and Methods: We described the morphology of this human right lower third molar at both the outer enamel surface and the enamel–dentine junction by means of micro‐computed tomography. In order to better understand hominin diversity, our morphological and metrical results were compared with those of other hominins obtained from published research. We provide a direct aspartic acid racemization dating of the molar. Results: The direct dating (104.3 ka) situates the molar within the Marine isotopic stage 5d. The crown dimensions are comparable to those of the Sima de los Huesos sample and modern humans. The combination of a continuous middle trigonid crest and a well‐developed anterior fovea lies within the range of morphological variation reported for Neanderthal lower molars. The distal portion of the molar has a prominent protostylid. Discussion: Crown and root morphology of this molar fits within the Neanderthal morphological pattern. However, both its dimensions and the absence of a hypoconulid tend to position this specimen away from contemporaneous Neanderthals and rather relate it more closely to some Middle Pleistocene populations. Conclusions: A new dental specimen is added to the Iberian Peninsula fossil record from the Marine isotopic stage 5, attesting to some degree of dental variability in the early Upper Pleistocene. [ABSTRACT FROM AUTHOR]

The coastal area between the mouths of the Aguas and Antas Rivers presents a deformed system of raised marine deposits, some of which have been strongly affected by active tectonics. The use of amino acid epimerization dating of Glycymeris shells from raised coastal deposits allowed determining the age of these marine deposits, all of them linked to highstand sea levels in the Mediterranean realm, with ages between MIS 11 and MIS 1. These results allowed corroborating the age of some previously studied sites, and using new sampling sites, the general aminostratigraphy for the Quaternary raised marine deposits on the Mediterranean coast was confirmed. The main deformation event took place after MIS 11 and continued until MIS 5, and was linked to the activity of the Palomares Fault. [ABSTRACT FROM AUTHOR]

Sedimentological, paleobiological, mineralogical, and geochemical analyses of a sediment core retrieved on the seafront of Cartagena Bay were performed after high-resolution sampling. A wide series of dates obtained through radiocarbon and amino acid racemization proved that the Holocene record on the analyzed core began at ca. 7300 yr cal BP. Reinterpretation of the marine seismic profiles indicated that the beginning of this transgression was channeled along erosive paleochannels excavated on a coastal plain of, at least, MIS5c age. The Holocene paleoenvironmental evolution consisted of a first period marked by marine conditions with strong inputs from a fan delta linked to the reorganized fluvial network that occurred after the sudden rise of the base level, which caused a growing sedimentary prism. Later, the full marine environment was reflected in the development of a Posidonia - Cymodocea meadow hosting a rich biodiversity of marine species (mollusks, foraminifera, ostracoda). Around 3800 yr cal BP, the area underwent a profound change and a silting process started to alter the conditions, turning the area into a paucispecific brackish marsh environment in which mud deposition was dominant. Since Carthaginian times, arrangement works locally affected the record, allowing the arrival of some marine species due to port work (dredging) undertaken to gain depth and showing anthropic influence. [ABSTRACT FROM AUTHOR]

At the northern tip of the Betic realm (SE Iberian Peninsula), some troughs (synclines) and elevations (anticlines) alternate, marking the present-day coastal lobed morphology of cape-bounded bays, where subsidence and uplift conditions prevailed, respectively. In this study, we were able to establish a clear coastal evolution. To this end, we considered the sedimentological and palaeoenvironmental conditions, the palaeogeographical reconstruction, and recent tectonics until Middle Pleistocene times (MIS 5) through the interpretation of onshore cores, raised marine deposits and geophysical profiles. In this regard, as reflected by both onshore and offshore information, there seems to be a stratigraphical gap from the end of the Pliocene to MIS 15 (Middle Pleistocene). In areas under uplift conditions, linked to tardive Alpine tectonics, the deposits of ancient shorelines and raised beaches were located at different post-depositional elevations, which were dated from odd MIS 15 to MIS 5 using amino acid racemization. Only deposits aged MIS 7 and MIS 5 are roughly at the present-day sea level or some meters above. In the troughs, which remain mostly as lagoons and salt marshes, subsidence did not allow the sedimentary record to be discerned. However, many borehole cores were recovered, attesting lagoonal, marsh, sabkha, or alluvial environmental conditions, which were usually unconnected from the sea. Micropaleontological and amino acid racemization dating revealed these cores to be of MIS15 to MIS5 age. Offshore seismic research revealed five erosive-bounded deposits that are stacked accretionary prisms corresponding to highstands between odd MIS 15 and MIS 5. In contrast, even MISs can be correlated to the erosive horizons that separated the seismic units, reflecting lowstands. In this regard, some bars, at a range of distances from the present-day coastline, protected wetlands from marine influence, allowing the development of diverse sub-environments under changing paleogeographical and paleoclimatological conditions. • Deposits of ancient shorelines and raised beaches were AAR dated from odd MIS 15 to 5. • MIS 7 & MIS 5 deposits are roughly at the present-day sea level or some meters above. • Ancient bars protected wetlands from marine influence allowing some sub-environments. • Offshore erosive-bounded deposits (stacked accretionary prisms) ensued in highstands. • Subsidence and uplift prevailed during Quaternary in the Iberian Mediterranean realm. [ABSTRACT FROM AUTHOR]

• Based on alkane indices, three geochemical units (GU) were identified. • GUs represent major contribution of aquatic macrophytes or terrestrial plants. • Paleoenvironmental episodes (PE) produced oscillations in the marsh water level. • PEs were related to sea level and climatic changes, and recent tectonics. • Emersion led to increased amounts of short-chain and branched fatty acids. We reconstructed the paleoenvironmental conditions of the Mazarrón Basin during MIS 7 and MIS 1 based on their alkane and fatty acid contents, their mineralogy and the fossil content of an amino-acid-dated sediment sequence. The n- alkane and fatty acid indices proved to be excellent paleoenvironmental proxies for studying the paleo-hydrogeological and paleoclimatological evolution of this marshland. Three geochemical units (GUs) were identified from the abundance of the C 25 n -alkane and the ACL, TAR HC and P aq values, confirming the importance of phases with terrestrial plant input or aquatic macrophyte predominance. These GUs were used to define three paleoenvironmental episodes (PEs) during MIS 7. In PE7.1, the contribution of algal and aquatic macrophytes predominated in a temporarily flooded saline muddy plain. In PE7.2, the major contribution was from aquatic macrophytes (flooded marsh), although it was marked by episodes of emersion with greater terrestrial contribution. At the top of the MIS 7 record (PE7.3), there was a significant reduction in the water depth, with the main input deriving from terrestrial plants in a muddy alluvial plain. Six PEs were established during MIS 1 (Holocene), of which three predominately received organic matter derived from aquatic macrophytes, while the major contribution in the other three came from terrestrial plants. The two sets of PEs were linked to episodes of increased and decreased water level, respectively. This interpretation is consistent with the characteristics of the sediment facies, with PE1.1, 1.3 and 1.5 corresponding to a marsh with deeper water and a greater input of detrital materials, and PE1.2, 1.4 and 1.6 to a shallow environment with carbonates and gypsum deposits. Direct marine influence was limited, so the oscillations in the water level in the marsh were likely to be more related to climatic changes (drier/wetter phases) and recent tectonics than to large changes in sea level. Emersion led to degradation of the organic matter and enrichment in short-chain and branched saturated fatty acids. [ABSTRACT FROM AUTHOR]

This paper presents a detailed geological and geomorphological analysis of the so‐called givoni (low‐relief, mainly gravelly landforms subparallel to the coastline) associated with the MIS 5 terrace in the northern Gulf of Taranto (southern Italy). These landforms can be interpreted as former beach ridges, swash/drift‐aligned spits, or swash/drift‐aligned barriers (BSBs); thus, givoni are palaeoshoreline indicators. In the study area, recognizing the classic landforms associated with marine terraces, that is, surfaces and scarps, is difficult, as the givoni are often associated and variably combined with surfaces and scarps. Thus, we reconstruct the formation and evolution processes of the MIS 5 marine terrace, including the formation of surfaces, scarps, and BSBs (and the resulting composite landforms), in an overall evolutionary framework based on eustatic oscillations. Then, we reconstruct a complete set of situations in which BSBs form on loose or semiconsolidated substrates in response to eustatic oscillations: (a) BSBs can form during a highstand of a warm stage on previously consolidated sediment; (b) BSBs may represent coastlines formed during sea‐level standstills in the context of a general regressive phase following the highstand peak that created a relict sea cliff; (c) BSBs may represent coastlines formed during a new relative highstand in a warm substage on previously unconsolidated deposits formed during the same stage; and (d) BSBs may be formed by a process similar to that of the previous case, except that the sea level stopped rising against a pre‐existing BSB. [ABSTRACT FROM AUTHOR]

The predominantly carbonate nature of the mountains near the coast of Málaga and Marbella (Costa del Sol, southern Spain) and the presence of springs have favored the formation of travertine buildups during the Quaternary. The geomorphic characteristics of the slopes and the location of the springs have determined the development of three types of travertine growths: (1) spring travertines, located preferentially on the south mountainside, where the slope is steepest; (2) pool-dam-cascade travertines, which form along the north and east edges, far from the carbonate relief and with a gentler slope; and (3) river-valley travertines, formed in the courses of the springs of any sector. Field observations combined with new amino acid racemization (AAR) dating of Helicidae gastropods show that most of the travertine formations are polyphasic and that their development was interrupted by stages of erosion and incision. Five stages of travertine development are evident, most of which are related to warm, moist episodes corresponding to marine oxygen isotope stages (MIS) 7, 5, 3, and 1, although local travertine growth also occurred during MIS 6 and during the transition from MIS 3 to 2. [ABSTRACT FROM AUTHOR]

Abstract The terrains of the Western Costa del Sol in the westernmost Mediterranean represent an outstanding example of the influence of major tectonic and climatic factors in the development of the landscape. This region belongs to the Alboran domain, which is a small continental lithosphere fragment embedded between the large Eurasian and African plates. The territory between Malaga and Marbella is composed mainly of the Sierra de Mijas and three adjacent subsidence areas: Malaga, Torremolinos, and Fuengirola basins. From the late Miocene, dip-faults of approximate directions N-S, NE-SW and NW-SE limited the Sierra de Mijas with respect to the adjacent subsidence areas and have marked the main features of the coastal morphology. Since then, the Sierra underwent mainly erosive processes linked to strong uplifting, while the surrounding basins were subjected to alternate stages of sedimentation and erosion. Thus, the paleogeographic and geomorphological evolution has been driven both by the regional tectonics and by significant base-level changes ranging from the spectacular Messinian low-stand to the catastrophic overflow at Gibraltar, followed by the global Late Tertiary and Quaternary sea-level changes. In the mountain relief, three different erosive leveling surfaces have been recognized, which developed in a staggered sequence during the Miocene, and are currently fragmented by tectonics at different elevations. The first two leveling surfaces, continental in origin, were carved during the Middle Miocene pro-part. The late one, correlating with Upper Miocene marine deposits from the Malaga basin, appears to correspond partially to an abrasion platform developed during the highstand of the late Tortonian. The strong incision of the fluvial network, especially due to the low sea-level during the Messinian salinity crisis, but also to the tectonic rise of the Sierra, has largely eroded these surfaces, which can be recognized only in narrow inter-fluvial areas. The noteworthy marine transgression in the Miocene-Pliocene transition reached the edge of the Sierra de Mijas, developing both a broad marine abrasion platform around it and the main stage of sedimentary filling in the Malaga basin. Tectonics combined with sea-level changes influenced the formation of a lower, second abrasion platform in the Torremolinos sector and along the S edge of the Sierra, showing continuity with the late Zanclean marine deposits in the Torremolinos and Fuengirola areas. During most of the late Pliocene and the Gelasian, the region remained emerged and subjected to erosion. Conversely, climate-eustatic changes throughout the Pleistocene and Holocene led to the development of three major generations of progradant alluvial fans interrupted by stages of erosion and incision of the fluvial network. In parallel, up to five episodes of travertine build-up occurred, usually coinciding with the humid and warm, odd-numbered isotopic stages. Highlights • Neogene tectonics form the main features of the landscape of the Costa del Sol. • The MSC and Pliocene re-flooding left strong traces in the relief of the region. • Quaternary climate cycles drive the development of alluvial fans and travertine. [ABSTRACT FROM AUTHOR]

To refine knowledge about terrace phases and uplift history for a tectonically poor deformed region, we apply the synchronous correlation method to reconstruct the chronology of a poorly constrained sequence of raised palaeoshorelines on the Apulian foreland, southern Italy. This work uses new chronological constraints obtained by amino acid racemisation (AAR) and isoleucine/alloisoleucine epimerisation (IE) on Patella spp., Thetystrombus latus (Gmelin), Glycymeris sp., and ostracods and U-series dating on corals Hoplangia durotrix Gosse and Cladocora caespitosa Linneo. This procedure provides a quantitative estimate of the vertical movements and associated rates within a region of the Apulian foreland. The synchronous correlation method uses sea-level highstands and uplift rate(s) as inputs; in particular, for sea-level highstands, the inputs are the age of the highstands and the sea-level elevation of the highstands relative to the present-day sea level. The output is a set of currently expected elevations of each sea-level highstand (the present elevations of palaeoshorelines). We then used regression analysis to assess the robustness between our observed palaeoshorelines and expected elevations of sea-level highstands. Our results show that the best fitting scenario is obtained using the sea-level curves of (i) Waelbroeck et al. (2002) from present to 410 ky BP and (ii) Rohling et al. (2014) from 410 to 590 ky BP as inputs for our synchronous correlation method, with uplift rates ranging from 0.09 mm/y to 0.07 mm/y with a mean value of 0.08 mm/y from 590 ky BP onwards. We recognised palaeoshorelines in the field belonging to the following highstands: 120 ky BP (MIS 5.5, second peak), 127 ky BP (MIS 5.5, first peak), 212 ky BP (MIS 7.3), 330 ky BP (MIS 9.3), 410 (MIS 11), 525 ky BP (MIS 13.3), and 590 ky BP (MIS 15). Our results show field observations of the reoccupation effect of younger palaeoshorelines over older ones due to the relatively slow uplift rates measured in the investigated area as predicted by our synchronous correlation method. In particular, we show a well-mapped and described reoccupation of the MIS 5.5 palaeoshoreline over the MIS 7.3 palaeoshoreline, constrained by new absolute dating. In addition, the data from the Apulian foreland suggest an MIS 7.3 highstand close to the present sea level. • We apply the synchronous correlation method in order to reconstruct palaeoshorelines. • Three palaeoshorelines dating back to two highstand of MIS 5.5 • Re-occupation of older palaeoshorelines by younger due to low uplift rates • Sea level for the MIS 7.3 highstand close to the present sea level [ABSTRACT FROM AUTHOR]

In this work, we reconstruct a change in the wind regime and sea level pressure pattern during marine isotope stage (MIS) 5.5. To obtain these results, we studied two elements of the landscape south of the city of Gallipoli (Apulia region, southern Italy), namely, the Carmine-Li Foggi palaeo-littoral ridge (CLlr) and a field of domal-longitudinal fossil dunes present in the Il Campo locality, both dating back to MIS 5.5, through the use of geological and geomorphological surveys together with geochronological analyses by Uranium series and amino acid racemization/epimerization. A detailed study was carried out on the aeolian units within CLlr (AU1 and AU2) and the fossil dunes of the Il Campo locality (AU3) to reconstruct the palaeo-directions of the winds and, possibly, the sea level pressure patterns. AU1 was the first aeolian unit to settle. The accumulation of AU1 at the northern and southern edges of CLlr and its internal structure indicate effective aeolian transport both towards the N and S. Based on the principle of actualism,the AU1 unit allows us to recognise a "first aeolian phase" characterised by the alternation of winds from the S and NW. It involves an autumn–winter pressure pattern characterised by an Atlantic footprint similar to the current pattern: the Atlantic depressions entering the Mediterranean caused, as occurs today over Apulia, the alternation of winds from the S and NW before and after the passage of the low-pressure minima, respectively. In spring–summer, the pressure fields were likely very similar to the current pressure fields, with the Azores high dominating the central–western Mediterranean and the low pressure dominating the eastern Mediterranean, with winds not able to significantly impact sand transport, just as occurs today; this summer regime left the prevailing imprint of the Atlantic winter regime and therefore NW–S bimodality. AU2 and AU3 settled later than AU1 in a "second aeolian phase" of MIS 5.5. AU2 is characterised by south-eastward-dipping foresets. AU3 consists of domal and linear dunes oriented in the NW–SE direction. We interpret AU2 and AU3 as coastal dunes originating in a prevailing NW wind regime. Based on the principle of actualism and on literature data, we conclude that AU2 and AU3 settled under a pressure pattern which in fall–winter was similar to the current pattern, that is, characterised by Atlantic cyclones transiting over the Mediterranean, and the consequent NW–S bimodality of the winds. In the spring–summer, instead, the pattern was characterised by a pressure gradient from west (high) to east (low) higher than the current pressure gradient; this gradient caused stronger NW winds compared to today over the Apulia, according to a similar (but increased) mechanism which today, on the Aegean Sea, causes the development of the Etesio-Meltemi summer winds. Such strong summer winds from the NW, which were effective for sand transport, coupled with the NW–S bimodality in fall–winter, caused the overall prevalence of NW winds during the "second aeolian phase". This summer pressure gradient over the Mediterranean from west (high) to east (low) greater than today was caused by a summer strengthening of the east Mediterranean low-pressure branch, in turn caused by the northward shift of the intertropical convergence zone (ITCZ), which was widely documented during the sapropel S5 event and verified during MIS 5.5 after sea level had risen to the highstand. • Geological and geomorphological study of coastal MIS 5.5 deposits of Apulia (Italy). • Change in the wind regime and pressure pattern during MIS 5.5. • First "aeolian phase" of MIS 5.5 characterised by the alternation of winds from the S and NW. • Second "aeolian phase" of MIS 5.5 characterised by NW prevailing winds. • Summer pressure gradient over the Mediterranean from west to east greater than today. • Summer pressure gradient greater than today due to northward shift of ITCZ. [ABSTRACT FROM AUTHOR]

We determined the lipid distributions ( n- alkanes, n- alkan-2-ones, n- alkanoic acids), total organic carbon (TOC), total nitrogen (TN), Ca/Mg and ash content in Las Conchas mire, a 3.2 m deep bryophyte-dominated mire in Northern Spain covering 8000 cal yr BP. Bog conditions developed in the bottom 20 cm of the profile, and good preservation of organic matter (OM) was inferred from n- alkanoic acid distribution, with the exception of the uppermost 20 cm (last ca. 200 yr). Microbial synthesis of long chain saturated fatty acids from primary OM likely produced a dominance of short chain n- alkanoic acids with a bimodal distribution, as well as the lack of correspondence between the n -alkane and n -alkanoic acid profiles in the upper 20 cm. This was accompanied by an increase in ash content, a decrease in TOC and variation in n- alkane ratios, thereby suggesting significant changes in the mire, namely drainage and transformation to a meadow, in the last ca. 200 yr. The distribution of n- alkan-2-ones indicated an increase in bacterial source from the bottom of the record to 94 cm, whereas their distribution in the upper part could be attributed mainly to plant input and/or the microbial oxidation of n- alkanes. The different n- alkane proxies showed variations, which we interpreted in terms of changes in vegetation (Sphagnum vs. non-Sphagnum dominated phases) during the last 8000 cal yr BP. C 23 was the most abundant homolog throughout most of the record, thereby suggesting dominant humid conditions alternating with short drier phases. However, such humid conditions were not linked to paleoclimatic variation but rather to geomorphological characteristics: Las Conchas mire, at the base of the Cuera Range, receives continuous runoff—even during drier periods—which is not necessarily accompanied by additional mineral input to peat, producing the development of Sphagnum moss typical of waterlogged ecotopes and damp habitats. Thus, although geochemical proxies indicated an ombrotrophic regime in the mire, geomorphological characteristics may make a considerable contribution to environmental conditions. [ABSTRACT FROM AUTHOR]

In this paper, we conduct a palynological analysis of a high-resolution Holocene record from Cartagena Bay, southeast of the Iberian Peninsula, to establish paleoenvironmental variability of coastal areas in the western Mediterranean region at a centennial-scale over the last 7300 years. Statistical analysis of four palynozones allows reconstruction of paleotemperature and paleohumidity conditions. Pinus , steppic, xerophilous, and Mediterranean taxa persisted continuously through the record, and only during periods of increased humidity did deciduous and Mediterranean taxa expand (Zones II, subzone IIIb). Cooler and dry conditions favored the development of Cupressaceae and scrubs between 7300 and 7000 yr cal BP. The mid-Holocene (Northgrippian) mesophytic optimum took place between 6800 and 4000 yr cal BP during which time a Mediterranean climate was present and open forest developed, predominantly consisting of Mediterranean taxa and deciduous trees. The gradual rise in aridity in the Meghalayan (4000–1700 yr cal BP) led to Mediterranean forest being replaced by steppic and xerophilous vegetation, a change related mostly to a decrease in summer insolation, with superimposed centennial-scale variability in humidity. In parallel with forest degradation caused by increasing aridity, the record shows marked evidence of human influence since 4000 yr cal BP, which accelerated the progression of open landscapes from the Chalcolithic onwards, this change being especially marked during the Roman period. Significant denudation of the landscape can be attributed to the use of fire, as well as due to agriculture and grazing, with a major contributor being intense metallurgical and mining activity in the area. The Cartagena Bay record reported herein shows centennial-scale oscillations in humidity and temperature that correlate with well-known climatic events during the late Holocene in the western Mediterranean region, synchronous with variability in solar and atmospheric dynamics. The alternation of persistent North Atlantic Oscillation modes is likely to have played a key role in regulating humid–arid periods. • Pollen content allowed the paleoenvironmental reconstruction during the Holocene. • Centennial-scale oscillations in humidity & temperature correlate with climatic events. • The mid-Holocene mesophytic optimum took place between 6800 and 4000 yr cal BP. • Aridity and xerophytization occurred between 4000 and 1700 yr cal BP. • Human influence accelerated the progression of open landscapes since the Chalcolithic. [ABSTRACT FROM AUTHOR]

A multiproxy study based on sedimentology, mineralogy, magnetic susceptibility, organic geochemistry and fossil content allowed to establish the sedimentary evolution of palustrine basins and to study the interplay between tectonic and climatic forcings in the sedimentation and facies arrangement that can be extrapolated to other coal-bearing basins. The reinterpretation of the data from 18 cores allowed to determine the facies distribution and to model the sedimentary evolution of the Padul Basin, with the longest continuous continental Quaternary record in the Southwestern Mediterranean region. The Padul Basin sediment record and facies successions provide an outstanding example of tectonically and environmentally controlled sedimentation. The sedimentary characteristics of the cores and thickness distribution revealed that recent tectonics was a more important forcing than other processes (e.g. climate). The influence of recent tectonics was determinant in facies arrangement, that is to say that the activity of a rotated fault produced a differential subsidence, causing more than 100 m of palustrine deposits to stack. On the basis of the sedimentological record combined with data on the mineralogy, fossil content, magnetic susceptibility and total organic carbon, three main sedimentary units were identified, linked to diverse subsidence rates and paleoenvironmental oscillations. The magnetic susceptibility was likely to have been controlled by the organic matter content (TOC values), linked to oxic/anoxic conditions. In the lower part of the record, Unit A (107.0–68.7 m), shallow lacustrine conditions were dominant, with an important influx associated with considerable runoff from active alluvial fans, linked to a higher subsidence rate. Unit B (68.7–37.6 m) had a transitional character, with a considerable decrease in the influence of the alluvial fan system. The lake recharge through overland flow markedly diminished and pre-existing groundwater recharge was dominant. A sudden change to peaty materials indicated that surface runoff was directly diverted to the recently excavated Dúrcal River gorge, thereby precluding the basin from becoming a swampy environment with stagnant waters. Unit C (upper 37.6 m) was almost exclusively fed by bicarbonate groundwater and subsurface runoff through the highly permeable coarse alluvial fan deposits. Within these main sedimentary units, minor mud-peat shallowing-upward sequences were identified. • The facies distribution and sedimentary evolution model along 1 Ma were determined • Recent tectonics was the dominant forcing and determinant in facies arrangement • The Garrido rotated Fault produced a differential subsidence at the NE corner • Sedimentary units showed distinct hydrogeological patterns linked to recent tectonics • Lacustrine conditions dominated at >400 ka; palustrine conditions occurred at <400 ka [ABSTRACT FROM AUTHOR]

The Tajo Basin is one of the richest in Mg-clays known around the world. Mg-bentonites, kwon as pink clays and green clays, alter in the Intermediate Unit of the Miocene sediments. In this work, a new approach to the genesis of these bentonites is performed by studying for the first time the biomarkers present in these clays in relation to the mineralogy and geochemistry, as well as using discriminatory criteria between green and pink clays. Samples were collected at a quarry of Mg-bentonites, in the proximities of Esquivias (Toledo, Spain). Mineralogical characterization and semi-quantification (X-ray diffraction (XRD)) allowed a well-defined classification according to the mineralogical content of the samples to be established, differentiating four associations. Geochemical analyses are clearly linked to the mineralogy and provide criteria to differentiate the genesis of the materials studied. In this regard, green clays are interpreted as having a more detrital character than pink clays, which present a more authigenic character. Biomarkers (n-alkanes and n-alkanoic acids) were studied, not showing a clear link with the mineralogy as in the case of the geochemistry, but providing interesting information about the origin and degradation of the organic matter. Pink clays have higher contents in biomarkers than green clays, providing a discriminative criterion. [ABSTRACT FROM AUTHOR]