We present new thermometers and barometers based on clinopyroxene-liquid equilibria specific to 37 alkaline differentiated magmas. The new models were calibrated through regression analyses of 38 experimental datasets obtained by merging phase equilibria experiments from literature with new 39 experiments performed by using trachytic and phonolitic starting compositions. The regression 40 strategy was twofold: i) we have tested previous thermometric and barometric equations and 41 recalibrated these models using the new datasets; ii) we have calibrated a new thermometer and a 42 new barometer including only regression parameters that closely describe the compositional 43 variability of the datasets. The new models yield more precise estimates than previous 44 thermometers and barometers when used to predict temperatures and pressures of alkaline 45 differentiated magmas. We have tested the reliability of the new equations by using clinopyroxene-46 liquid pairs from trachytes and phonolites erupted during major explosive eruptions at the Phlegrean 47 Fields and Mt. Vesuvius (central Italy). The test yielded crystallization conditions comparable to 48 those determined by means of melt and fluid inclusion analyses and phase equilibria studies; this 49 validates the use of the proposed models for precise estimates of crystallization temperatures and 50 pressures in differentiated alkaline magmas. Because these magmas feed some of the most 51 voluminous, explosive, and threatening volcanic eruptions in the world, a better understanding of 52 the environmental conditions of their reservoirs is mandatory and this is now possible with the new 53 models provided here. 54 55 56 table 2 Click here to download table: Table 2.doc

We present the first integrated tephrochronological study (major and trace elemental glass composition, Sr and Nd isotope analyses, and 40Ar/39Ar dating) for the last one tenth (∼82 m) of the ∼900 m-thick Quaternary lacustrine succession of the Fucino Basin, the largest and probably only Central Apennine intermountain tectonic depression that hosts a continuous lacustrine succession documenting the Plio-Quaternary sedimentary history up to historical times. Major element glass compositions, determined using a wavelength-dispersive electron microprobe (WDS-EMPA), yielded the geochemical fingerprinting needed for a reliable identification of most of the 23 stratigraphically ordered tephra layers under investigation. These include tephra from Italian volcanoes such as Campi Flegrei, Etna, Colli Albani, Ischia, Vico, Sabatini, and undefined volcanic sources in the Neapolitan area and Latium region. The recognition of key Mediterranean marker tephra layers (e.g. X-5 and X-6) is supported by trace element data acquired by Laser Ablation Inductively Couple Plasma Mass Spectrometry (LA-ICP-MS). The Sr and Nd isotope compositions of selected layers where also determined for circumscribing the volcanic source of distal tephra and for supporting correlations with individual eruptive units. We also propose a new, more expeditious covariation diagram (CaO/FeOtot vs Cl) for identifying the volcanic source of trachytic to phonolitic and tephrytic to phonolitic tephra, that are the most common compositions of pyroclastic rocks from volcanoes of Campania and Latium regions. Finally, we present five new 40Ar/39Ar age determinations, including a new, analytically well-supported, and more precise 40Ar/39Ar age for the widespread Y-7 tephra, and the first 40Ar/39Ar age determinations for one tephra from the Sabatini volcanic district (∼126 ka) and one tephra from Neapolitan volcanic area (Campi Flegrei?; ∼159 ka). These newly dated tephra are widely dispersed (e.g. Monticchio, southern Italy, Adriatic Sea and Lake Ohrid, Macedonia-Abania) and have thus the potential to become important Mediterranean MIS 5 and MIS 6 tephrochronological markers. Altogether the new geochemical data and 40Ar/39Ar ages precisely constrain the chronology of the investigated Fucino succession spanning the last ∼190 ka. In light of these results and by considering that this sedimentary succession possibly extends back to ∼2 Ma, Fucino is likely to provide a very long, continuous tephrostratigraphic record for the Mediterranean area and become a key node in the dense network of tephra correlations of this region

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Here we present the first tephrostratigraphic, palaeomagnetic, and multiproxy data from a new ~98 m-deep sediment core retrieved from the Fucino Basin, central Italy, spanning the last ~430 kyr. Palaeoenvironmental proxy data (Ca-XRF, gamma ray and magnetic susceptibility) show a cyclical variability related to interglacialglacial cycles since the Marine Isotope Stage (MIS) 12-MIS 11 transition. More than 130 tephra layers are visible to the naked eye, 11 of which were analysed (glass-WDS) and successfully correlated to known eruptions and/or other equivalent tephra. In addition to tephra already recognised in the previously investigated cores spanning the last 190 kyr, we identified for the first time tephra from the eruptions of: Tufo Giallo di Sacrofano, Sabatini (288.0 ± 2.0 ka); Villa Senni, Colli Albani (367.5 ± 1.6 ka); Pozzolane Nere and its precursor, Colli Albani (405.0 ± 2.0 ka, and 407.1 ± 4.2 ka, respectively); and Castel Broco, Vulsini (419-490 ka). The latter occurs at the bottom of the core and has been 40 Ar/ 39 Ar dated at 424.3 ± 3.2 ka, thus providing a robust chronological constrain for both the eruption itself and the base of the investigated succession. Direct 40 Ar/ 39 Ar dating and tephra geochemical fingerprinting provide a preliminary radioisotopic-based chronological framework for the MIS 11-MIS 7 interval, which represent a foundation for the forthcoming multiproxy studies and for investigating the remaining ~110 tephra layers that are recorded within this interval. Such future developments will be contribute towards an improved MIS 11-MIS 7 Mediterranean tephrostratigraphy, which is still poorly explored and

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