Two-stage progression of volcanism (8–0 Ma) in the central Mediterranean (southern Italy)

Abstract

The latest Pliocene–Present (2–0 Ma) evolution in the central Mediterranean, southern Italy, is illustrated as the second stage of a two-stage magmatic progression which affected the back-arc domain of the southern Tyrrhenian sea as well as its corresponding foreland of eastern Sicily and Strait of Sicily. The first stage took place from late Miocene to late Pliocene (ca. 8–2 Ma). In the Tyrrhenian back-arc eruption of E-MORB type lavas (Vavilov basin) predated volcanism exhibiting calcalkaline and Na-alkaline affinity which is located in arc and in passive margin setting, respectively. In the same period the Sicilian foreland was affected by magmatic activity of subalkaline (tholeiitic) and Na-alkaline nature with intraplate signature. The second stage was from the latest Pliocene (2 Ma) to Present. In the time span 2–1.5 Ma, tholeiitic volcanism concomitantly affected the Marsili back-arc basin and the northern margin of the Iblei plateau in eastern Sicily. The next magmatic pulse (1–0 Ma) saw the effusion of calcalkaline volcanics in the active Aeolian arc and Marsili seamount (southern Tyrrhenian sea), of rift-related Na-alkaline rocks to the west of them, and of the lavas of the Mount Etna (Sicilian foreland). The two stages of magmatic activity reflect the convergent geodynamic evolution in the central Mediterranean and appear to be controlled by discontinuous pulses of decoupling and roll-back of the subducting Ionian oceanic lithosphere, which became progressively steeper in time.