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We adopted a combined geophysical-stratigraphic approach to identify grain size anomalies in sediment distribution of the Bagnoli coastal brownfield site. A large industrial plant occupied this area during most of the 20th Century. We used 18 core logs to identify macroscopic variation in sediment stratigraphy, and 72 supplemental cores to mark changes between sandy- and silt-dominated intervals. The stratigraphy evidenced the presence of anomalous lens of silt within a sandy coastal sector inside the Bagnoli industrial harbour. Cores description helped us to calibrate the interpretation of 4 subbottom profiles, that we used to obtain information on geometries of silty deposits. The spatial layout of sediments revealed that silt intervals are present in the area bounded by the old industrial wharfs. We suggest that these silty sediments are likely the result of uncontrolled discharge occurred during the last century. Once calibrated, high-resolution mono-channel seismic profiles helped us to define the shape as well as the real extent and thicknesses of silty deposits, resulted to be ca. 515.000 m2, with an overall volume of 480.000 m3. These results are a first attempt to define the amount of polluted sediments in the area facing the Bagnoli industrial harbour. [ABSTRACT FROM AUTHOR]

The climate evolution of the last 2700 years in the central - western Mediterranean Sea has been reconstructed from marine sediment records by integrating planktonic foraminifera and geochemical signals. The results provide the characterization of six climatic phases: Balearic Bronze Age (BA), Roman Period (RP), Dark Age (DA), Medieval Climate Anomaly (MCA), Little Ice Age (LIA) and Industrial Period (IP). Paleoclimatic curve inferred from planktonic foraminifera associated with heavy values in δ 18 O Globigerinoides ruber during the BA document two cold intervals (spanning ca. 200 years) related to the Homeric and Greek solar minima. The dominance of Turborotalita quinqueloba –Globigerinita glutinata gr. and Globigerina bulloides during the RP suggest high fertility surface waters condition probably triggered by the increase in precipitation. During the DA, changes in the foraminiferal paleoclimate curve and oxygen isotope values display a cold –dry phase from 700 CE to the end of the DA (ca. 850 CE). This phase corresponds to the cold Roman IV solar minimum and marks the beginning of a long - term cooling interval that terminates during the LIA. The MCA is characterized by mild climatic conditions, interrupted at ca. 1050 CE by a cold - dry event. The gradually increase in abundance of G. ruber white characterize the IP warm period. The reconstructed climate evolution in the Balearic Basin results almost time - equivalent with the Mediterranean climate variability over the last 2700 years. [ABSTRACT FROM AUTHOR]

We present a high-resolution paleoclimatic and paleoenvironmental reconstruction of the last five millennia from a shallow water marine sedimentary record from the central Tyrrhenian Sea (Gulf of Gaeta) using planktonic foraminifera, pollen, oxygen stable isotope, tephrostratigrapy and magnetostratigrapy. This multiproxy approach allows to evidence and characterize nine time intervals associated with archaeological/cultural periods: Eneolithic (base of the core–ca. 2410 BCE), Early Bronze Age (ca. 2410 BCE–ca. 1900 BCE), Middle Bronze Age–Iron Age (ca. 1900 BCE–ca. 500 BCE), Roman Period (ca. 500 BCE–ca. 550 CE), Dark Age (ca. 550 CE–ca. 860 CE), Medieval Climate Anomaly (ca. 860 CE–ca. 1250 CE), Little Ice Age (ca. 1250 CE–ca. 1850 CE), Industrial Period (ca. 1850 CE–ca. 1950 CE), Modern Warm Period (ca. 1950 CE–present day). The reconstructed climatic evolution in the investigated sedimentary succession is coherent with the short-term climate variability documented at the Mediterranean scale. By integrating the planktonic foraminiferal turnover from carnivorous to herbivorous–opportunistic species, the oxygen isotope record and the pollen distribution, we document important modification from the onset of the Roman Period to the present-day. From ca. 500 CE upwards the documentation of the cooling trend punctuated by climate variability at secular scale evidenced by the short-term δ 18 O is very detailed. We hypothesise that the present day warm conditions started from the end of cold Maunder event. Additionally, we provide that the North Atlantic Oscillation (NAO) directly affected the central Mediterranean region during the investigated time interval. [ABSTRACT FROM AUTHOR]

The volcanism of back-arc basins resembles that of oceanic spreading centers, rifts, and, in vanishing stages, extensional arcs, depending on the amount and rate of the dynamic processes associated to the subduction. Marsili Seamount (MS) represents the axial ridge of the Southern Tyrrhenian Sea back-arc basin, which is connected to the slab roll-backing processes affecting the Calabrian Arc (Italy). The Southern Tyrrhenian Sea back-arc is characterized by a significant decline in the spreading rate with time (2.8–3.1 mm/a to less than 1.8 mm/a in the last 0.78–1 Ma). MS develops between about 1 Ma and 3 ka and mainly consists of lava flows erupted from central and fissural vents. The MS products belong to the calcalkaline association and range in composition from basalts to trachytes. We present new stratigraphic, geochronological, and geochemical data (glass shards and minerals) of tephra from a 2.35 m long gravity core (Marsili1 core) recovered on MS at 943 m b.s.l. We recognize five tephras [M1 (top of the core) to M5 (bottom)] represented by poorly to highly vesiculated ashes. The lowermost tephra M5 emplaced between ca. 7 and 26 ka B.P.; it represents the less evolved distal counterpart of the Unit D related to the Biancavilla–Montalto products of Mount Etna (Sicily). The M1 to M4 tephras emplaced between 2.1 and 7.2 ka B.P. and are related to strombolian-like submarine eruptions of NNE–SSW aligned MS vents. The composition of the M1–M4 glasses ranges from basaltic trachyandesites to andesites and trachytes. The M1 to M4 magmas mainly originated by crystal fractionation from a heterogeneous mantle source with varying LILE enrichments by subduction-related fluids. The degree of evolution of the MS magmas increases with decreasing time. The formation of vertically stacked magma storage zones at the crust/mantle interface and within MS is related to the vanishing Southern Tyrrhenian Sea opening, which implies the rapid (< 1 Ma) evolution from a slow spreading back-arc setting to an arc system. [ABSTRACT FROM AUTHOR]

Bagnoli-Coroglio is a Site of National Interest (SNI) facing the Pozzuoli Bay that has been the place of an industrial activity for more than a century (1854-1985). The modern coastal geology of this area results from the recent evolution of an antecedent volcanic landscape that originated after a caldera collapse following the eruption of Neapolitan Yellow Tuff (NYT) of Campi Flegrei (15 ka). After the NYT eruption, a shallow marine depression formed within the caldera collapse area that underwent progressive filling-up, due to volcaniclastic sediment input from the caldera borders, within a semi-enclosed source-to-sink system. The integrated interpretation of the Digital Terrain Model (DTM) of the Bagnoli-Coroglio area and the high resolution reflection seismic profiles acquired off the Pozzuoli Bay suggests that the present-day coastal plain of Bagnoli-Fuorigrotta and conterminous continental shelf represent the latest infilling phase of the annular depression (caldera 'collar') between the structural border of the NYT caldera and the inner caldera resurgent dome. The stratigraphic architecture and morpho-bathymetry of the Bagnoli inner shelf provide a record of the complex interplay between eustatic sea level changes, volcano-tectonic (ground/seafloor) deformation, and supply of volcaniclastic sediments, with associated coastline shifts over the last millennia. [ABSTRACT FROM AUTHOR]

The analyses of water and sediment samples, collected at 24 marine stations in a coastal area (Gulf of Gaeta, central Tyrrhenian Sea) during a three year survey (2012–2014), have improved our knowledge of coccolithophore ecology in the Mediterranean neritic domain. A comparison between the results and the oceanographic data has highlighted the ecology of the considered groups, and quantified the relationship between the community structures and the environmental parameters. The coccosphere concentration measured in the Gulf of Gaeta is extremely variable over the sampling periods (min:64 l −1 ; max:2.4*10 5  l −1 ), and comparable with data from other Mediterranean sites. Placolith-bearing taxa are the dominant group of the living communities. The concentration and distribution of Emiliania huxleyi is controlled by the distance from the coast and the Volturno River runoff. The K-strategist taxa are an important component of the summer nannoplankton in the upper 15 m and in the sediment samples. These taxa are also related to summer oligotrophic warm waters and low turbidity as well. The opportunistic behaviour of Helicosphaera carteri is confirmed and is related to moderately elevated nutrient levels and also tolerance to low salinity and terrigenous input. Nevertheless, our findings raise some questions on the reliability of H. carteri as a low salinity proxy. Overall, the sediment assemblages reflect the composition and the temporal distribution of the living communities. The occurrence and distribution of abundant reworked coccoliths, both in water and sediments, provides useful information about coastal dynamics and confirm their use as a reliable runoff proxy. [ABSTRACT FROM AUTHOR]

We present the results of a high resolution study carried out on a shallow water sediment core, recovered in the central Tyrrhenian Sea to reconstruct the runoff history of the catchment basin of Volturno and Garigliano rivers (Gulf of Gaeta, Italy), over the past ~ 400 years. We compared the abundance distribution pattern of Reworked Coccoliths to the surface runoff model simulation for the Volturno and Garigliano hydrographic river basins, the Global Historical Climatology Network index, the Palmer drought severity index, the Tevere river discharge anomaly, the average summer rainfall in Southern Italy and the reconstructed North Atlantic Oscillation signal. This comparison suggested that the biotic signal of the Reworked Coccoliths may be used to detect climatic events from local to “global” scale. The calcareous nannofossil assemblages as well as their diversity index are modulated by oscillation in solar activity, where minima in solar activity correspond to minima calcareous nannofossil diversity and vice versa . In particular, the antiphase correlation between the abundance of Reworked Coccoliths and the North Atlantic Oscillation index, which modulates winter precipitation, suggests that this biotic index could be used as a reliable proxy to reconstruct the variations in the hydrographic basin runoff of the Volturno and Garigliano rivers. In addition, power spectral and wavelet analysis carried out on both signals documented the occurrence of climatic cycles of the duration of about 95 yr. From 1900 AD upwards, a turnover in the periodicity from 95 yr climatic cycles to 22–26 yr cycles occurred in the Reworked Coccoliths signal, suggesting a strong control of solar forcing (Hale cycle) over the last century. [ABSTRACT FROM AUTHOR]

We present the distribution pattern of living and surface sediment coccolithophores, the main phytoplankton calcifying group, from 22 stations set in a neritic environment (from 10 to 50 m water depth), adjacent to the shelf area of the Volturno River mouth (Gulf of Gaeta - central part of the Tyrrhenian Sea). The survey conducted in June 2012 included five transects perpendicular to the coast, which enabled us to provide indications on the structure of calcareous phytoplankton associations in relation to coastal dynamics and the Volturno River runoff. The total number of coccospheres ranged from 15 to 64 * 10³* l-1 coccolithophores. Emiliania huxleyi dominates the assemblages, followed by Rhabdosphaera xiphos, holococcolithophores and Syracosphaera pulchra. The coccolithophore community shows a typical vertical zonation, with K-strategist taxa in the upper 15 m and the deep community developed down to 40 m. The local water circulation significantly affects the spatial and vertical distribution of coccolithophores. The river discharge influences the distribution of coccolithophore taxa, resulting in a north-south gradient. In the northern sector, outside the influence of the Volturno River, the high values of R. xiphos suggest a negative correlation with river runoff. The surface sediment assemblages reflect the overall composition of the living coccolithophore communities. The distribution of abundant reworked species, both in water and sediment, provides useful information about coastal dynamics and sediment transport in the study area. [ABSTRACT FROM AUTHOR]

Abstract: We present a major, trace and rare earth element characterization of single glass shards from fifteen tephra layers found in the astronomically-tuned KC01B deep-sea core (Ionian Sea, Central Mediterranean-36°15.25′N, 17°34.44′E, 3642 m water depth). KC01B is considered a reference core for the Mediterranean area since it provides a new reliable astronomical tuned timescale for the last 1.112 My (Lourens, 2004). The studied deposits punctuate the marine record in a time span ranging from ca 16 ka to ca 191 ka B.P. encompassing the climatic zones Y, X, W and V. They are related to volcanic activity of the Campania Plain, Aeolian Islands, Mt. Etna and Pantelleria Island. Along with major main markers of the Central Mediterranean area such as Y-1, Y-5, and X-6, astronomically dated at 16.7 ka, 39.1 ka, and 110.5 ka, respectively, the succession contains a number of well preserved deposits which can represent useful inter-archive instruments of correlation. The Campania Plain, in particular, sourced at least nine compositionally homogeneous tephra layers prior to the Campanian Ignimbrite event. The data obtained in this work provide a new detailed analytical reference database for Ionian Sea tephrochronology and for proximal-distal correlation studies. They may help to unravel from the marine record the history of poorly known or unknown explosive activity on land since the middle Pleistocene along with chemical composition, size and dispersal of the products. [Copyright &y& Elsevier]

Abstract: A high-resolution integrated stratigraphy is presented for the Late Quaternary in the southern-eastern Tyrrhenian Sea. It is based on calcareous plankton taxa (planktonic foraminifera and nannoplankton) distribution, δ18O G lobigerinoides ruber record, tephrostratigraphy and radiometric dating methods (210Pb and 137Cs, AMS 14C) for a composite sediment core (from the top to the bottom, C90-1m, C90 and C836) from the continental shelf of the Salerno Gulf. High sedimentation rates from ca 1 cm/100 y for the early Holocene, to 3.45 cm/100 y for the middle Holocene to 8.78 cm/100 y from late Holocene and to 20 cm/100 y for the last 600 AD, make this area an ideal marine archive of secular paleoclimate changes. Quantitative distributional trend in planktonic foraminifera identify seven known (1F–7F) eco-biozones, and several auxiliary bioevents of high potential for Mediterranean biostratigraphic correlation. Recognised were: the acme distribution of Neogloboquadrina pachyderma r.c. between 10.800 ± 0.400 ka BP and 5.500 ± 0.347 ka BP, a strong increase in abundance of Globorotalia truncatulinoides r.c. and l.c. at 5.500 ± 0.347 ka BP and at 4.571 ± 0.96 ka BP, respectively, an acme interval of Globigerinoides quadrilobatus (between 3.702 ± 0.048 ka BP and 2.70 ± 0.048 ka BP) and the acme/paracme intervals of T. quinqueloba (acme between 3.350 ± 0.054 ka BP and 1.492 ± 0.016 ka BP; paracme between 1.492 ± 0.016 ka BP and 0.657 ± 0.025 ka BP; acme beginning 0.657 ± 0.025 ka BP). These results, integrated with trends of selected calcareous nannofossil species (Florisphaera profunda, Brarudosphaera bigelowii, Gephyrocapsa oceanica and Emiliania huxleyi) and δ18O G. ruber signature, are consistent with the most important pre-Holocene and early Holocene paleoclimatic and paleoceanographic phases i.e., the Bölling–Allerod, the Younger Dryas and the time interval of Sapropel S1 deposition in the eastern Mediterranean Sea. These features revealed the high potential of this shallow water environment for high-resolution stratigraphy and correlation for the western Mediterranean. In addition, the chemical characterization of seven tephra layers supplied further data about the age and the dispersal area of some well-known Campi Flegrei explosive events, inferring the possible occurrence of explosive activity at Vesuvius around the middle of the 6th century, and contributing to refine the tephrostratigraphic framework for the last 15 ka in the south-eastern Tyrrhenian Sea. [Copyright &y& Elsevier]

Abstract: Astronomical calibration of the lower–middle Pleistocene Montalbano Jonico section located in the Lucania Basin (Southern Italy) is presented. Previous papers widely discussed the integrated stratigraphy (calcareous nannofossils, sapropel stratigraphy, benthic and planktonic oxygen stable isotopes) and the paleoenvironmental features of this section and its potential suitability for the selection of the Middle Pleistocene Global Stratotype Section and Point (GSSP). In this study, new planktonic δ18O data, additional biostratigraphical constraints and new tephrochronology on volcaniclastic layers occurring within the studied record are reported. The new chronostratigraphic framework provides a robust base for correlation of the oxygen isotope stratigraphy for the Montalbano Jonico section with the glacial and interglacial fluctuations of the Oceanic and Mediterranean δ18O reference deep-sea records. Specifically, the lower part of the Montalbano Jonico section (Interval A) provides correlation of the planktonic and benthic δ18O cycles to Marine Isotope Stage (MIS) 36 to MIS 23. Interval A includes a distinct peak of left-coiled neogloboquadrinids, the Globoratalia crassaformis influx, the First Occurrence of Gephyrocapsa omega, and the First Common Occurrence and Last Common Occurrence of Reticulofenestra asanoi. These stratigraphical constraints support the tuning of five sapropel layers included in this part of the section to insolation cycles i-112, i-104, i-102, i-90 and i-86. The upper part of the section (Interval B), which includes the temporary disappearance (td2) of G. omega and tephra layer V5, Ar/Ar age dated at 719.5±12.6ka, is consistent with identification of MIS 22 to MIS 16 in the planktonic δ18O pattern. The δ18O time series of the whole section was reconstructed using the midpoints of individual sapropels and their correlative precession minima, visual comparison of the δ18O pattern with the record available at the Mediterranean ODP Site 975, and, in the upper part of the section, the Ar/Ar age of tephra V5. The developed astronomical tuning revealed that the Montalbano Jonico section covers an interval from 1240ka to 645ka. A significant change in sedimentation rate occurs between Intervals A (0.53m/ky) and Interval B (0.91m/ky) at about 870ka and is consistent with a sea-level drop from a bathyal to a circalittoral environment. Bioevents recognised in the Montalbano Jonico section have been dated according to the astronomical calibration, and age assignments of tephra V1–V4 and V6–V9 are also proposed. The Montalbano Jonico section fills the gap between the top of the Vrica section and the base of the Ionian informal Middle Pleistocene stage, and represents a Mediterranean reference section for the Mid-Pleistocene transition. [Copyright &y& Elsevier]

Abstract: A quantitative analysis of planktonic foraminifera, coupled with petrophysical and paleomagnetic measurements and 14C-AMS calibrations, was carried out on a deep core recovered in the Sardinia Channel (Western Mediterranean Sea), during the CIESM Sub2 survey, providing an integrated stratigraphic time-framework over the last 80kyr. Significant changes in the quantitative distribution of planktonic foraminifera allowed the identification of several eco-bioevents useful to accurately mark the boundaries of the eco-biozones widely recognized in the Western Mediterranean records and used for large-scale correlations. Namely, 10 eco-biozones were identified based on the relative abundance of selected climate-sensitive planktonic foraminiferal species. Sixteen codified eco-bioevents were correlated with Alboran Sea planktonic foraminiferal data and several climatic global events (Sapropel S1, Younger Dryas, Greenland Isotope Interstadial 1, Greenland Isotope Stadial 2, Heinrich event H1–H6) were recognized. The eco-bioevents together with the 14C-AMS calibrations allowed us to define an accurate age model, spanning between 2 and 83kyr. The reliability of the age model was confirmed by comparing the colour reflectance (550nm%) data of the studied record with the astronomically tuned record from the Ionian Sea (ODP-Site 964). A mean sedimentation rate of about 7cm/kyr included three turbidite event beds that were chronologically constrained within the relative low stand and regressive sea-level phases of MIS 4 and 3. The deep-sea sedimentary record includes a distinct tephra occurring at the base of the core that dates 78kacal.BP. The paleomagnetic data provide a well-defined record of the characteristic remanent magnetization that may be used to reconstruct the geomagnetic paleosecular variation for the Mediterranean back to 83kyr. [Copyright &y& Elsevier]