The late Miocene – early Pliocene offshore onshore sedimentary records in the vicinity of Gibraltar

[EN] Atlantic gateways, progressively isolating the Mediterranean Basin from the Global Ocean. This change in gateway configuration modified radically the circulation patterns, water residence time and salinity of the Mediterranean waters leading to the extraordinary paleoenvironmental change known as the Messinian Salinity Crisis (MSC). This event lasted between 5.97 and 5.33 Ma and led to the deposition of huge evaporite accumulations both in the marginal and deep Mediterranean basins. Now, more than 50 years after the Glomar challenger ventured Mediterranean waters, and the evaporites in deep basins were discovered, the debate regarding the conditions and timing of the deposition of the Mediterranean salt giant is still ongoing as many theories regarding the dynamics and chronology of the Gibraltar arc gateway/s closure and reopening are waiting to be validated. In this optic, the study of cores and outcrops in the proximity of the current Strait of Gibraltar is essential to better understand the evolution of the Mediterranean – Atlantic gateways. In this thesis we perform a detailed planktic and benthic foraminifer, geochemical (XRF and stable isotopes) and sedimentological analyses of Alboran Basin ODP Site 976, DSDP Site 121, industrial boreholes Andalucia-G1, Alboran-A1, landbased sections from southern Spanish basins including Nijar, Sorbas and Malaga and Montemayor-1 core from the Guadalquivir Basin. The obtained results, paired with the interpretation of seismic profiles acquired in the Alboran Basin gave some new insights and results towards the better understanding of the Late Miocene to early Pliocene evolution of the Mediterranean – Atlantic gateways and the effects of the restriction on the Mediterranean environments before and after the MSC. The main outcomes of this thesis are outlined in the next paragraphs, as follows: → A high-resolution planktonic foraminifer stratigraphy performed on Sites 976 and Montemayor-1 in combination with the analyses of the astronomically driven cyclical changes in the geochemical record enabled the astronomical tuning of the two locations. Having a firm age model allowed to pinpoint the moment when the uplift of the Gibraltar arc gateway/s started affecting the Mediterranean Basin and Betic corridor. → The first sign of the Mediterranean – Atlantic gateway restriction is visible in the Mediterranean basin from 7.17 Ma, when active tectonism at the Gibraltar arc started uplifting the Betic and Rifian corridors. At ODP Site 976, the uplift is visible from the increase in terrigenous input arriving to the Alboran basin and parallel higher sedimentation rates related with an increased river erosion. On the other hand, the shift from benthic foraminifer open-marine high oxygen fauna to shallow infaunal taxa, tolerant to a wide range of conditions and suboptimal oxygen levels, paired with a significant drop in benthic δ13C values suggests that the gateway restriction led to the decrease in bottom water oxygen levels and increase in its residence time much earlier than the onset of the MSC. → A correlation between data from ODP Site 976 and other Mediterranean records confirmed that the 7.17 Ma gateway restriction, affected at the same time different locations all over the Mediterranean, inferring a Mediterranean-scale change in thermohaline circulation. From these data we concluded that the West Alboran Basin (WAB) and the East Alboran Basin (EAB) were not separated by a sill at that time but were both part of the Mediterranean realm. Furthermore, it was possible to create a refined Mediterranean circulation model for before and after the 7.17 Ma event. → The gateway restriction registered in the Mediterranean record since 7.17 Ma, is visible also from the geochemical data of Montemayor-1 core in the Guadalquivir Basin. Because the geochemical data from Montemyor-1 reveals that after 7.15-7.17 Ma, the Guadalquivir Basin was bathed by only one water mass, probably Atlantic, we believe that the connection between the Mediterranean and Atlantic through the Betic corridor was restricted at that time. Consequently, we suggest that the restriction of the last Betic gateway, the Guadalhorce Basin, could have happened at 7.15-7.17 Ma and caused the abovementioned changes in the Mediterranean paleoenvironment. → Because the gateway restriction was contemporaneous with the global Late Miocene Carbon Isotope Shift (LMCIS) it was important to discern between global and local effects and compare the Mediterranean and global records. Given the synchronism of the global and local Mediterranean change in the δ13C record, a global effect certainly affected the Mediterranean Basin. However, opposite phase relations of the global and local δ13C signals with orbital parameters, paired with a higher magnitude change identified in our WAB isotope record suggests that the local imprint overruled the global one. A similar effect can be seen in the Montemayor-1 record, where apart from the changes related to the uplift of the Gibraltar arc, a global signal cannot be overruled. → Finally, through the development of this thesis it is shown how the dark layer often enriched in organic matter, present at the Miocene – Pliocene boundary in several Mediterranean marginal and deep basins, suggests that the Zanclean reflooding created water column stratification, and reduced bottom water oxygen levels. Such stratification could be the result of a sinking of more saline Atlantic water mass entering into a less saline Mediterranean Basin still under the influence of the Paratethys. The benthic foraminifer repopulation sequence identified at the base of the Pliocene shows similarities with more recent events of repopulation of hostile environments or following low-oxic episodes during sapropel deposition. However, Atlantic values of the benthic δ13C registered in the Alboran Basin suggest that bottom water renewal and circulation were efficient during the early Zanclean, preventing the reduction of δ13C at the seafloor seen after 7.17 Ma. Furthermore, the slight discrepancies in the benthic foraminifer repopulation sequences of the marginal basins at the Miocene – Pliocene boundary, and the much lighter benthic δ13C values in the Malaga Basin can suggest a diachronous reflooding of the shallower marginal basins

Bronze Age to Roman period salt production in the coastal areas of peninsular Italy:Palaeoenvironments, production methods and archaeological evidence

The landscape characteristics and salt production methods along the coasts of peninsular Italy from the Bronze Age to the Roman period are examined, with a focus on the significance of marine salt for Italy's ancient food economy, given the limited availability of rock salt. Two main methods of marine salt production are highlighted. Briquetage involves using clay or pottery containers to evaporate seawater, which requires specific environmental conditions such as clay availability and significant human labour and technological skill. Conversely, salterns consist of creating shallow ponds or pools for seawater evaporation, demanding flat coastal areas, a stable climate, and controlled seawater flow. While this method is less labour-intensive, it requires substantial initial infrastructure. The potential for salt production in Italy's coastal palaeoenvironments using either method has been evaluated. Key factors include coastal geomorphology, climate stability, and access to raw materials. This environmental data supports an analysis of archaeological remains from salt production sites active from the Bronze Age to the Roman period. The assessment focuses on the material evidence such as clay containers from briquetage and structural remains of salterns, aiming to understand the spatial and temporal distribution of these sites. The discussion also explores the geopolitical implications of salt production, examining how the distribution and development of these sites were affected by broader geopolitical shifts in Italy, including the impact of (proto)urbanization on the expansion and adaptation of salt production practices.</p

Mediterranean water in the Atlantic Iberian margin reveals early isolation events during the Messinian Salinity Crisis

Recent studies highlight the role of the Mediterranean Outflow Water (MOW), in the intensification of the Atlantic Meridional Overturning Circulation and as source of heat and salty water to high latitudes. During the Late Miocene the MOW suffered major changes and likely a total collapse during the Messinian Salinity Crisis (MSC). In order to study the MOW evolution in the Atlantic margin during the Tortonian-Messinian interval we completed a new high resolution geochemical and stable isotope record for the corresponding interval of the Montemayor-1 and Huelva-1 cores. Both sites are located in the Guadalquivir Basin on the former Atlantic side of the Mediterranean – Atlantic gateways (Iberian Atlantic margin) during the late Miocene. The tuning of this isotope record with astronomical solutions and other global isotope curves has allowed the establishment of an improved chronology and, consequently, to precisely date environmental changes happening on the Atlantic margin of the Iberian peninsula and their link to Mediterranean and global events. At 7.17 Ma, in concomitance with a shallowing of the basin, the residence time, temperature and salinity of the bottom waters increased. These changes were related to a reduction of the MOW reaching the Atlantic side as a consequence of the restriction of the last strand of the Betic corridor that connected the Mediterranean and the Atlantic. This hypothesis is in line with the analogous changes observed in several Mediterranean Sea locations, where from 7.17 Ma onward a reduced Mediterranean – Atlantic connection is observable. Furthermore, the new isotope chronology sheds light, through comparison with other records, on the age of Messinian geomagnetic reversals.</p

Mediterranean water in the Atlantic Iberian margin reveals early isolation events during the Messinian Salinity Crisis

Recent studies highlight the role of the Mediterranean Outflow Water (MOW), in the intensification of the Atlantic Meridional Overturning Circulation and as source of heat and salty water to high latitudes. During the Late Miocene the MOW suffered major changes and likely a total collapse during the Messinian Salinity Crisis (MSC). In order to study the MOW evolution in the Atlantic margin during the Tortonian-Messinian interval we completed a new high resolution geochemical and stable isotope record for the corresponding interval of the Montemayor-1 and Huelva-1 cores. Both sites are located in the Guadalquivir Basin on the former Atlantic side of the Mediterranean – Atlantic gateways (Iberian Atlantic margin) during the late Miocene. The tuning of this isotope record with astronomical solutions and other global isotope curves has allowed the establishment of an improved chronology and, consequently, to precisely date environmental changes happening on the Atlantic margin of the Iberian peninsula and their link to Mediterranean and global events. At 7.17 Ma, in concomitance with a shallowing of the basin, the residence time, temperature and salinity of the bottom waters increased. These changes were related to a reduction of the MOW reaching the Atlantic side as a consequence of the restriction of the last strand of the Betic corridor that connected the Mediterranean and the Atlantic. This hypothesis is in line with the analogous changes observed in several Mediterranean Sea locations, where from 7.17 Ma onward a reduced Mediterranean – Atlantic connection is observable. Furthermore, the new isotope chronology sheds light, through comparison with other records, on the age of Messinian geomagnetic reversals.</p

Predict: Assessing the Seismic Response in the city of Rome, Part 1. New Data for a Geologic Overview

This work presents the preliminary results of the stratigraphic, paleomagnetic, micropaleontologic and geochronologic investigations carried out on the cores of three boreholes performed in the historic center of Rome within the Predict Project, aimed at evaluating the seismic response within the City through the 3D modeling of the subsoil. Moreover, we have integrated the investigations on the cores of four previously performed boreholes and we use this larger dataset to provide an objective element for the interpretation and validation of a large databank of paper stratigraphies of boreholes carried out for civil engineering purposes in the Roman area. The new data are presented within an exhaustive review of state of the art on the scientific knowledge on the geology of Rome, aimed at providing an updated background for the Quaternary scientists, seismologists, engineers and professional technicians operating in this region. Within this framework, we provide a detailed reconstruction of the chronostratigraphic setting in central Rome, highlighting a coherent picture within the glacio‐eustatic control on the sedimentary processes and providing the background geological input data for the creation of a geo‐database in a dynamic GIS environment, which is the subject of a forthcoming sister‐paper

Predict:Assessing the Seismic Response in the city of Rome, Part 1. New Data for a Geologic Overview

This work presents the preliminary results of the stratigraphic, paleomagnetic, micropaleontologic and geochronologic investigations carried out on the cores of three boreholes performed in the historic center of Rome within the Predict Project, aimed at evaluating the seismic response within the City through the 3D modeling of the subsoil. Moreover, we have integrated the investigations on the cores of four previously performed boreholes and we use this larger dataset to provide an objective element for the interpretation and validation of a large databank of paper stratigraphies of boreholes carried out for civil engineering purposes in the Roman area. The new data are presented within an exhaustive review of state of the art on the scientific knowledge on the geology of Rome, aimed at providing an updated background for the Quaternary scientists, seismologists, engineers and professional technicians operating in this region. Within this framework, we provide a detailed reconstruction of the chronostratigraphic setting in central Rome, highlighting a coherent picture within the glacio-eustatic control on the sedimentary processes and providing the background geological input data for the creation of a geo-database in a dynamic GIS environment, which is the subject of a forthcoming sister-paper.</p

A tale of a changing basin: a transient model of the 7.17 event leading to the Messinian Salinity Crisis

Before the Messinian Salinity Crisis (MSC) left its imprint on the sediment record of the Mediterranean Sea in the form of evaporites, the basin had already undergone significant changes. At 7.17 Ma, a drop in δ13C values, as well as a basin-wide shift in the abundance of benthic foraminifers, already attest to a sudden change in the Mediterranean conditions. This event coincides with an increase in the amplitude of the insolation curve. It thus stands to question whether a change in the freshwater budget or a change in the connection between the Mediterranean Sea and the Atlantic was the driver for this event. Answering this question would not only help to understand the event itself, but might also help to decipher the early dynamics of the MSC. With a computational box model, we investigate the response of the Mediterranean Sea to a varying freshwater budget for a wide range of restriction. The results then let us define scenarios in which we analyse how a gradually changing restriction would express itself in the basin dynamics. We find that the change in the freshwater budget alone cannot explain the changes that are attributed with the 7.2 event, but coupled with an increase in restriction most differences can be accounted for. Our results also show that a gradual change in restriction can provoke a non-linear response in the behaviour of the basin, which can appear abrupt when happening on a short enough timescale. Such a change would also enhance the influence of said changes in the freshwater budget. This tells us that the processes that most likely triggered the Messinian Salinity Crisis started much earlier and incrementally increased the restriction of the Mediterranean Sea

Relevance of CD49d protein expression as overall survival and progressive disease prognosticator in chronic lymphocytic leukemia

CD49d/α4-integrin is variably expressed in chronic lymphocytic leukemia (CLL). We evaluated its relevance as independent prognosticator for overall survival and time to treatment (TTT) in a series of 303 (232 for TTT) CLLs, in comparison with other biologic or clinical prognosticators (CD38, ZAP-70, immunoglobulin variable heavy chain (IGHV) gene status, cytogenetic abnormalities, soluble CD23, β2-microglobulin, Rai staging). Flow cytometric detection of CD49d was stable and reproducible, and the chosen cut-off (30% CLL cells) easily discriminated CD49dlow from CD49dhigh cases. CD49d, whose expression was strongly associated with that of CD38 (P < .001) and ZAP-70 (P < .001), or with IGHV mutations (P < .001), was independent prognosticator for overall survival along with IGHV mutational status (CD49d hazard ratio, HRCD49d = 3.52, P = .02; HRIGHV = 6.53, P < .001) or, if this parameter was omitted, with ZAP-70 (HRCD49d = 3.72, P = .002; HRZAP-70 = 3.32, P = .009). CD49d was also a prognosticator for TTT (HR = 1.74, P = .007) and refined the impact of all the other factors. Notably, a CD49dhigh phenotype, although not changing the outcome of good prognosis (ZAP-70low, mutated IGHV) CLL, was necessary to correctly prognosticate the shorter TTT of ZAP-70high (HR = 3.12; P = .023) or unmutated IGHV (HR = 2.95; P = .002) cases. These findings support the introduction of CD49d detection in routine prognostic assessment of CLL patients, and suggest both pathogenetic and therapeutic implications for CD49d expression in CLL

Mediterranean biodiversity gradient initiated by basin restriction

Physical connectivity between marine basins facilitates population exchange and hence controls biodiversity. The Mediterranean Sea is a semi-restricted basin with only a small two-way connection to the global ocean, and it is a region heavily impacted by climate change and biological invasions today. The massive migration of non-indigenous species into the basin through the Suez Canal, driven and enabled by climate warming, is drastically changing Mediterranean biodiversity. Understanding therefore the origin and cause(s) of pre-existing biodiversity patterns is crucial for predicting future impacts of climate change. Mediterranean biodiversity exhibits a west-to-east decreasing gradient in terms of species richness, but the processes that resulted in this gradient have only been hypothesized. By examining the fossil record, we provide evidence that this gradient developed 5.33 million years ago at the end of the Messinian Salinity Crisis, and it was therefore caused by the re-population of the basin by marine species with a dominating western source at the Mediterranean¿Atlantic gateway