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A high-resolution integrated study has been performed in a super-expanded marine record (sedimentation rate spanning from 11 cm/100 years to 20 cm/100 years) from the continental shelf area of the southeastern Tyrrhenian Sea. Planktonic foraminiferal distribution illustrates 6 major environmental changes during the past 2000 years: (i) the Roman Period-Dark Age transition (from herbivorous-opportunistic to carnivorous species); (ii) the Dark Age-MCA transition (from carnivorous to herbivorous-opportunistic species); (iii) the Medieval Classic Anomaly-Little Ice Age transition (a further and definitive change from carnivorous to herbivorous-opportunistic species); (iv) the period during the Maunder event between approximately 1720 AD and 1740 AD (turnover from the carnivorous planktonic foraminifer Globigerinodes ruber to the herbivorous-opportunistic planktonic foraminifer Turborotalita quinqueloba); (v) the Industrial Period (dominance of herbivorous-opportunistic planktonic foraminifera); and (vi) the Modern Warm Period at approximately 1940 AD (the last turnover in favor of herbivorous-opportunistic planktonic foraminifers, associated with an increase in benthic foraminifera). Our studies lead us to link this latter feature to an anthropogenic impact associated with the damming of Sele River (Salerno Gulf) at 1934 AD, which induced a change in the sediment input with a strong decrease in coarse-grained fraction and a probable alteration in nutrient supply. The δ18O G. ruber record of the past 2000 years shows the alternation of warm/wet and cold/dry events related to the Roman Period, the Dark Age, the Medieval Classic Anomaly, the Little Ice Age, the Industrial Period and the Modern Warm Period. The 5 evident δ18O G. ruber oscillations (between approximately 1325 AD and 1940 AD) coincide with the 5 minima in the solar activity record (Wolf, Spörer, Maunder, Dalton and Damon events). [ABSTRACT FROM AUTHOR]

A sequence of tephra layers is studied in a 13.9 m-long deep-sea core (MD01-2474G) from the southern Tyrrhenian Sea. The chronology of the succession is provided by a high-resolution age-depth model based on isotope stratigraphy and AMS radiocarbon dating, which place the succession of events in a time interval spanning the last 70 ka. Based on a precise chronological framework and proximal-distal correlations, the Y-1, Y-6 and Y-7 main marker tephras were identified. Compositional data on fresh micro-pumice or glass shards of selected tephras were correlated with the coeval volcanic activity of Aeolian Arc (Vulcano and Salina), Mt. Etna, Phlegrean Fields Pantelleria and Ischia. The tephra sequence contains a number of deposits documenting recurrent activity on Vulcano Island at ca. 6.9 ka BP (MD3), ca. 16.7 ka BP (MD11), ca. 23.2 ka BP (MD14), ca. 29.6 ka BP (MD15), ca. 36.9 ka BP (MD22) and ca. 42.5 ka BP (MD27). The results presented in this study improve the southern Tyrrhenian Sea tephrostratigraphic framework and provide new insights into chemistry and dispersal area of Aeolian Arc pyroclastic deposits in this sector of the Central Mediterranean. [ABSTRACT FROM AUTHOR]

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]