Magmatic History of Somma–Vesuvius on the Basis of New Geochemical and Isotopic Data from a Deep Borehole (Camaldoli della Torre)

Abstract

A continuous-coring borehole recently drilled at Camaldoli dellaTorre on the southern slopes of Somma^Vesuvius provides constraints on the volcanic and magmatic history of the Vesuvian volcanic area since c. 126 ka BP.The cored sequence includes volcanic units, defined on stratigraphical, sedimentological, petrological and geochemical grounds, emitted from both local and distal vents. Some of these units are of known age, such as one Phlegraean pre-Campanian Ignimbrite, Campanian Ignimbrite (39 ka), Neapolitan Yellow Tuff (149 ka) and Vesuvian Plinian deposits, which helps to constrain the relative age of the other units.The main rock types encountered are shoshonite, phonotephrite, latite, trachyte and phonolite. The sequence includes, from the base upwards: a thick succession of pyroclastic units emplaced between 126 and 39 ka, most of them attributed to eruptions that occurred in the Phlegraean area; the Campanian Ignimbrite; the products of a local tuff cone formed between 39 ka and the deposition