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The Christiana-Santorini-Kolumbo volcanic field (CSKVF) in the Aegean Sea is one of the most active volcano-tectonic lineaments in Europe. Santorini has been an iconic site in volcanology and archaeology since the 19th century, and the onshore volcanic products of Santorini are one of the best-studied volcanic sequences worldwide. However, little is known about the chronology of volcanic activity of the adjacent submarine Kolumbo volcano, and even less is known about the Christiana volcanic island. In this study, we exploit a dense array of high-resolution marine seismic reflection profiles to link the marine stratigraphy to onshore volcanic sequences and present the first consistent chronological framework for the CSKVF, enabling a detailed reconstruction of the evolution of the volcanic rift system in time and space. We identify four main phases of volcanic activity, which initiated in the Pliocene with the formation of the Christiana volcano (phase 1). The formation of the current southwest-northeast–trending rift system (phase 2) was associated with the evolution of two distinct volcanic centers, the newly discovered Poseidon center and the early Kolumbo volcano. Phase 3 saw a period of widespread volcanic activity throughout the entire rift. The ongoing phase 4 is confined to the Santorini caldera and Kolumbo volcano. Our study highlights the fundamental tectonic control on magma emplacement and shows that the CSKVF evolved from a volcanic field with local centers that matured only recently to form the vast Santorini edifice.

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Unintentional parathyroidectomy, although common, has no clinical consequences. Unlike surgeon's experience and operative technique, patient sex was the only factor affecting its occurrence.

Caldera-forming eruptions of island volcanoes generate tsunamis by the interaction of different eruptive phenomena with the sea. Such tsunamis are a major hazard, but forward models of their impacts are limited by poor understanding of source mechanisms. The caldera-forming eruption of Santorini in the Late Bronze Age is known to have been tsunamigenic, and caldera collapse has been proposed as a mechanism. Here, we present bathymetric and seismic evidence showing that the caldera was not open to the sea during the main phase of the eruption, but was flooded once the eruption had finished. Inflow of water and associated landsliding cut a deep, 2.0–2.5 km3, submarine channel, thus filling the caldera in less than a couple of days. If, as at most such volcanoes, caldera collapse occurred syn-eruptively, then it cannot have generated tsunamis. Entry of pyroclastic flows into the sea, combined with slumping of submarine pyroclastic accumulations, were the main mechanisms of tsunami production.

Detailed single-channel continuous seismic reflection profiling data from four gulfs as well as onshore neotectonic investigations have allowed the study of the neotectonic structure of the Hellenic arc along a complete transverse section from its external area in the trench to the internal back-arc area.It is the direct continuation of the continental slope from the trench to the island arc (Peloponnesus, Crete, Dodekannese). Argolikos Gulf is an almost symmetric NW-SE graben occupying the northern edge of the Cretan back-arc basin. Saronikos Gulf is a multi-complex structure of a NW-SE graben in the SW (Epidaurus Basin) and alternation of E-W horsts and grabens in the North. Its neotectonic evolution is characterized by the Plio-Quaternary volcanic arc activity. Southern Evoikos Gulf is a relatively shallow neotectonic graben in the back-arc area at the northern prolongation of the Cycladic Platform.Each of the above neotectonic basins has its own characteristics which are probably due to their geodynamic position in the Hellenic arc. In general, there is a decrease in the neotectonic deformation, the sediment thickness and the sedimentation rates from SW to NE, going from the periphery to the core of the arc.Messiniakos Gulf is an asymmetric NW-SE structure with considerable tilt towards the NE.