Field of Science

New and past volcanic islands in the Mediterranean Sea

Researches of the INGV (Istituto Nazionale di Geofisica e Vulcanologia) and the University of Calabria have announced that a previously unknown volcanic mountain was detected in the Tyrrhenian Sea, 120m below sea level off the coast of Calabria in the area surrounding Capo Vaticano (38° 50' N; 15° 50' E).
The results of the aeromagnetic and geological survey will be published in the upcoming Journal of Geophysical Research (JGR). The researchers followed a "trackway" of ancient volcanic deposits of unknown origin in the area of Capo Vaticano, finally extending their search with a geomagnetic survey into the sea.
The radiometric dating of the pumice on land also gives an approximate phase of activity for the new unnamed volcano of 670.000 to 1 million years ago.
The volcano is situated on a tectonic fault zone, and is thought to represent an extension to the east of the volcanic arc of the Aeolian Islands, an interesting observation that maybe will have important influence on the understanding of the general configuration of plate margins in the Tyrrhenian Sea.


The presence of submarine volcanoes is not unusual in the surroundings of Italy and especially Sicily. In the canal of Sicily, between the Italian island and the African coast, a number of volcanic mountain ranges are know, thought to be the remains of an increased volcanic activity one million years ago. The island of Pantelleria for example is only one of the most prominent and highest peaks in the region. In July 1831 a secondary volcanic aperture of the main volcanic complex of "Empedocles" (named after the Greek naturalist) erupted and reached sea level, forming a cone up to 60m high. The property of the new formed island soon became a dispute between France, who named it Julia, England, who named it Graham, and Sicily, who named it Ferdinandea (the introducing figure depicts an artistic rendering of the 1831 eruption). The controversy got resolved after 5 months, when the island was completely eroded by the action of the waves. Today the peak of the island lays 6m below sea level, after an increased tectonic activity between 1980 and 2000 raised it by 2m.
The weak, but ongoing volcanic activity of Ferdinandea in 1987 fooled even the crew of an American vessel, misinterpreting the rumours caused by the volcano for a hostile submarine; they decided to bomb it...

References:

VENÈ, M (2003): La Miniatlantide Siciliana. In: Vulcani d´Italia. Supplemento allegato al N. 262 di Airone Febbraio 2003

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