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Anecdotes of concurrent eruptions at Etna, Stromboli, and Vulcano (Southern Italy) have persisted for more than 2000 years and volcanologists in recent and past times have hypothesized a causal link among these volcanoes. Here this hypothesis is tested. To introduce the problem and provide examples of the type of expected volcanic phenomena, narratives of the most notable examples of concurrent eruptions are provided. Then the frequency of eruptions at each individual volcano is analysed for about the last 300 years and the expected probability of concurrent eruptions is calculated to compare it to the observed probability. Results show that the occurrence of concurrent eruptions is often more frequent than a random probability, particularly for the Stromboli-Vulcano pair. These results are integrated with a statistical analysis of the earthquake catalogue to find evidence of linked seismicity in the Etnean and Aeolian areas. Results suggest a moderate incidence of non-random concurrent eruptions, but available data are temporally limited and do not allow an unequivocal identification of plausible triggers; our results, however, are the first attempt to quantify a more-than-2000-years-old curious observation and constitute a starting point for more sophisticated analyses of new data in the future. We look forward to our prediction of a moderate incidence of concurrent eruptions being confirmed or refuted with the passage of time and occurrence of new events.

A helicopter-borne experimental aeromagnetic survey, covering an area of 200 km2, was performed in the Volturno valley area north of the Roccamonfina volcano and south of Venafro in November 1994. Although severe logistical, instrumental and meteorological conditions significantly reduced the planned coverage, the processed magnetic image still shows a remarkable improvement in the description of the geological and structural features of the area in comparison with previous regional aeromagnetic data. A multi-directional shaded relief anomaly map displays two moderately positive NW magnetic bands associated with lavas, pyroclastics and dykes of the Roccamonfina volcanic district together with N-S, NNE-SSW and NE-SW lineations. A comparative magnetic-geologic map allows correlation with known Pleistocene faults and reveals the existence, especially in the area between Sesto Campano and Presenzano, of a larger presence of high susceptibility dykes than seen in the outcrop, which is dominated by non-magnetic carbonatic rocks. We interpret the curvilinear and intricate pattern of magnetic lineaments as suggestive of an extensional setting along the main NW structures with previous strike slip components and of tectonic activity along a N-S fabric; the latter has no superficial evidence and has also been used for magma upwelling. Overall, this local scale investigation shows both the utility and the need for further efforts in high resolution aeromagnetics in Italy both for geological and environmental purposes similar to those successfully carried out in many other countries throughout the world.

According to the historical sources, the Colosseum suffered several types of damage related to earthquakes. In particular, the damage is mostly concentrated in the southern portion of the amphitheater where the study of the geological features shows the presence of a Holocene alluvial valley, a situation that is potentially responsible for significant amplification of ground motion during earthquakes. A detailed reconstruction of the subsurface geology in the area of the Colosseum was performed with the purpose of verifyipg whether the heterogeneity of the damage observed could be associated with the variability of the geological conditions of the site where the monument was built.