THE CAPO ROSSELLO BORE-HOLE (AGRIGENTO, SICILY) CYCLOSTRATIGRAPHIC AND PALEOCEANOGRAPHIC RECONSTRUCTIONS FROM QUANTITATIVE ANALYSES OF THE ZANCLEAN FORAMINIFERAL ASSEMBLAGES

Cyclostratigraphy based on the quantitative analyses of planktonic foraminifera in the Zanclean segment (M Pl 1 base of M Pl 3 biozones) of the bore-hole drilled in the Capo Rossello area (Sicily, Southern Italy) allows us to recognize that the calcareous plankton biostratigraphic events occur in the same cycles as identified by previous authors. Exceptional thick cycles which are thought to represent two precession cycles show two fluctuations is greater than the number of lithologic cycles. Between the base of the Pliocene and the first occurrence of Globorotalia puncticulata thirty-five lithologic cycles and thirty eight planktonic foraminifera fluctuations are present. By comparison with relative abundance fluctuations in the benthic foraminifera and the astronomical record is recognized. In particular, the BN>125 µm and the Planulina ariminensis quantitative distributions are related to the long eccentricity. Conversely, the relative abundance fluctuations of Siphonina reticulata, Cibicidoides bradyi, Pullenia bulloides and Uvigerina pygmaea appear to be generally forced by the precession periodicity, but in the intervals coincident with the eccentricity minima such a relationship is less clear. The very abundant and widespread distribution in several Mediterranean sites of S. reticulata, which we consider a quasi-endemic species of this basin during the Early and Middle Pliocene is anticovariant with the quantitative distribution of Cibicidoides brady-robertsonianus, which is considered a characteristic species of the North Atlantic Deep Water (NADW). This relationship suggest that a peculiar, intermediate water mass was present in the Mediterranean during this time interval. We propose for this water mass the name of Early Pliocene Mediterranenan Intermediate Water (EPMIW). According to bibliographic data that report the sharp decrease in abundance of S. reticulata during the M Pl 5 biozone, EPMIW was present in the Mediterranean basin until about 2.5 Ma.&nbsp

THE CAPO ROSSELLO BORE-HOLE (AGRIGENTO, SICILY) CYCLOSTRATIGRAPHIC AND PALEOCEANOGRAPHIC RECONSTRUCTIONS FROM QUANTITATIVE ANALYSES OF THE ZANCLEAN FORAMINIFERAL ASSEMBLAGES

Cyclostratigraphy based on the quantitative analyses of planktonic foraminifera in the Zanclean segment (M Pl 1 base of M Pl 3 biozones) of the bore-hole drilled in the Capo Rossello area (Sicily, Southern Italy) allows us to recognize that the calcareous plankton biostratigraphic events occur in the same cycles as identified by previous authors. Exceptional thick cycles which are thought to represent two precession cycles show two fluctuations is greater than the number of lithologic cycles. Between the base of the Pliocene and the first occurrence of Globorotalia puncticulata thirty-five lithologic cycles and thirty eight planktonic foraminifera fluctuations are present. By comparison with relative abundance fluctuations in the benthic foraminifera and the astronomical record is recognized. In particular, the BN>125 µm and the Planulina ariminensis quantitative distributions are related to the long eccentricity. Conversely, the relative abundance fluctuations of Siphonina reticulata, Cibicidoides bradyi, Pullenia bulloides and Uvigerina pygmaea appear to be generally forced by the precession periodicity, but in the intervals coincident with the eccentricity minima such a relationship is less clear. The very abundant and widespread distribution in several Mediterranean sites of S. reticulata, which we consider a quasi-endemic species of this basin during the Early and Middle Pliocene is anticovariant with the quantitative distribution of Cibicidoides brady-robertsonianus, which is considered a characteristic species of the North Atlantic Deep Water (NADW). This relationship suggest that a peculiar, intermediate water mass was present in the Mediterranean during this time interval. We propose for this water mass the name of Early Pliocene Mediterranenan Intermediate Water (EPMIW). According to bibliographic data that report the sharp decrease in abundance of S. reticulata during the M Pl 5 biozone, EPMIW was present in the Mediterranean basin until about 2.5 Ma.&nbsp

a smart nanofibrous material for adsorbing and detecting elemental mercury in air

Abstract. The combination of the affinity of gold for mercury and nanosized frameworks has allowed for the design and fabrication of novel kinds of sensors with promising sensing features for environmental applications. Specifically, conductive sensors based on composite nanofibrous electrospun layers of titania easily decorated with gold nanoparticles were developed to obtain nanostructured hybrid materials capable of entrapping and revealing gaseous elemental mercury (GEM) traces from the environment. The electrical properties of the resulting chemosensors were measured. A few minutes of air sampling were sufficient to detect the concentration of mercury in the air, ranging between 20 and 100 ppb, without using traps or gas carriers (LOD: 1.5 ppb). Longer measurements allowed the sensor to detect lower concentrations of GEM. The resulting chemosensors are expected to be low cost and very stable (due to the peculiar structure), requiring low power, low maintenance, and simple equipment

The Global Stratotype Section and Point (GSSP) of the Serravallian Stage (Middle Miocene)

The Global Stratotype Section and Point (GSSP) for the Base of the Serravallian Stage (Middle Miocene) is defined in the Ras il Pellegrin section located in the coastal cliffs along the Fomm Ir-Rih Bay on the west coast of Malta (35°54'50"N, 14°20'10"E). The GSSP is at the base of the Blue Clay Formation (i.e., top of the transitional bed of the uppermost Globigerina Limestone). This boundary between the Langhian and Serravallian stages coincides with the end of the major Mi-3b global cooling step in the oxygen isotopes and reflects a major increase in Antarctic ice volume, marking the end of the Middle Miocene climate transition and the Earth's transformation into an "Icehouse" climate state. The associated major glacio-eustatic sea-level drop corresponds with sequence boundary Ser1 of Hardenbol et al. (1998) and supposedly with the TB2.5 sequence boundary of Haq et al (1987). This event is slightly older than the last common and/or continuous occurrence of the calcareous nannofossil Sphenolithus heteromorphus, previously considered as guiding criterion for the boundary, and is projected to fall within the younger half of Chron C5ACn. The GSSP level is in full agreement with the definitions of the Langhian and Serravallian in their respective historical stratotype sections in northern Italy and has an astronomical age of 13.82 Ma

COVID-19 lockdowns reveal the resilience of Adriatic Sea fisheries to forced fishing effort reduction

The COVID-19 pandemic provides a major opportunity to study fishing effort dynamics and to assess the response of the industry to standard and remedial actions. Knowing a fishing fleet’s capacity to compensate for effort reduction (i.e., its resilience) allows differentiating governmental regulations by fleet, i.e., imposing stronger restrictions on the more resilient and weaker restrictions on the less resilient. In the present research, the response of the main fishing fleets of the Adriatic Sea to fishing hour reduction from 2015 to 2020 was measured. Fleet activity per gear type was inferred from monthly Automatic Identification System data. Pattern recognition techniques were applied to study the fishing effort trends and barycentres by gear. The beneficial effects of the lockdowns on Adriatic endangered, threatened and protected (ETP) species were also estimated. Finally, fleet effort series were examined through a stock assessment model to demonstrate that every Adriatic fishing fleet generally behaves like a stock subject to significant stress, which was particularly highlighted by the pandemic. Our findings lend support to the notion that the Adriatic fleets can be compared to predators with medium-high resilience and a generally strong impact on ETP species

Rock magnetic signature of the Middle Eocene Climatic Optimum (MECO) event in different oceanic basins

The Middle Eocene Climatic Optimum (MECO) event at ~40 Ma was a greenhouse warming which indicates an abrupt reversal in long-term cooling through the middle Eocene. Here, we present environmental and rock magnetic data from sedimentary successions from the Indian Ocean (ODP Hole 711A) and eastern NeoTethys (Monte Cagnero section - MCA). The high-resolution environmental magnetism record obtained for MCA section shows an interval of increase of magnetic parameters comprising the MECO peak. A relative increase in eutrophic nannofossil taxa spans the culmination of the MECO warming and its aftermath and coincides with a positive carbon isotope excursion, and a peak in magnetite and hematite/goethite concentrations. The magnetite peak reflects the appearance of magnetofossils, while the hematite/goethite apex are attributed to an enhanced detrital mineral contribution, likely related to aeolian dust transported from the continent adjacent to the Neo-Tethys Ocean during a drier, more seasonal MECO climate. Seasurface iron fertilization is inferred to have stimulated high phytoplankton productivity, increasing organic carbon export to the seafloor and promoting enhanced biomineralization of magnetotactic bacteria, which are preserved as magnetofossils during the warmest periods of the MECO event. Environmental magnetic parameters show the same behavior for ODP Hole 711A. We speculate that iron fertilization promoted by aeolian hematite during the MECO event has contributed significantly to increase the primary productivity in the oceans. The widespread occurrence of magnetofossils in other warming periods suggests a common mechanism linking climate warming and enhancement of magnetosome production and preservation

Monitoring of cfrp-strengthened reinforced concrete bridge spans in low temperature conditions

The article discusses strengthening bridges using composite materials at extreme low temperatures. Provides the results some experimental studies FRP strengthened concrete samples at low temperatures

Mercury in fishes from Augusta Bay (southern Italy): Risk assessment and health implication

Our study reports on the total mercury (HgT) concentrations measured in the muscles and livers of several benthic, demersal and pelagic fish species caught inside and outside of Augusta Bay (southern Italy), a semi-enclosed marine area, highly contaminated by the uncontrolled (since the 1950s to 1978s) discharge of the largest European petrochemical plant. Mercury levels in fish tissues are discussed with regard to specific habitat, size and/or age of the specimens and HgT distribution in the bottom sediments. Results suggest a still active Hg release mechanism from the polluted sediments to the marine environment. Also, the high HgT concentrations measured in fishes caught in the external area of the bay imply a potential role of Augusta Bay as a pollutant source for the Mediterranean ecosystem. Finally, values of hazard target quotient (THQ) and estimated weekly intake (EWI) demonstrate that consumption of fishes caught inside the bay represents a serious risk for human health. Also, data indicate that intake of fishes caught from the external area of the bay, especially for that concern demersal and benthic species, could be represent a significant component of risk for the local population