For the next 8 weeks, the Research Vessel “POSEIDON” from the GEOMAR Helmholtz Centre for Ocean Research in Kiel, Germany, is studying the volcanoes of the Cyclades Islands in cooperation with researchers from the National and Kapodistrian University of Athens. Volcanic activity in the region of Santorini has been of great scientific interest, mostly because of the famous Minoan eruption of the late Bronze Age (∼3600 BP) and especially since the recent 1650 eruption at the submarine volcano Kolumbo. But tectonic forces that led to those events have been acting on this region for millions of years. To better understand the evolution of the volcanoes and find clues to possible future volcanic hazards, the German and Greek research team is studying their distant past.
Since March 8, the Research Vessel “POSEIDON” has been deploying an autonomous underwater vehicle or AUV, named ABYSS, in the waters between Santorini and Amorgos Island, mapping nearly 100 km2 of the seabed in the search for signs of past tectonic activity and submarine eruptions. The goal is to understand the process of rifting of the crust and how this leads to active volcanism, major earthquakes, and widespread hydrothermal activity at the seafloor. Prof. Mark Hannington, chief scientist of the expedition, notes “These processes have been acting on the region for millions of years, and some of the fine structures that we can now see in the AUV maps tell us a great deal about the possible future evolution of the volcanoes”. It is the first time that an active volcano in the Aegean Sea, like Kolumbo has been mapped at such a high resolution with an AUV.
During April, Dr. Joerg Geldmacher will use the remotely operated submersible PHOCA to dive from Poseidon to the volcanoes surrounding Santorini. For the next 3 weeks, he and his team will be collecting samples of volcanic rocks from the steep underwater cliffs to document the evolution of the magma intruded into the fault zones over the last million years. The ROV will also be used to produce the first high-resolution photomosaics of the volcano. In May, Dr. Armin Freundt will lead a final 2 week expedition to take cores of deep-sea sediments (up to 12 m) containing a record of highly explosive eruptions that have occurred in the last 160,000 years. These samples will help to quantify the hazards from past eruptions as a measure for risk from future volcanic activity.
The research program is a cooperation with Prof. Paraskevi Nomikou of the National and Kapodistrian University of Athens who has been leading research at Santorini and Kolumbo since 2010. “Our partnership with the German research team is helping us to advance our knowledge of the tectonic and volcanic activity in the area ”, says Nomikou.
RV “POSEIDON” will leave the Aegean at the end of May. Until then, it will be seen working in the waters around Santorini and the neighbouring islands, probing the past to better understand future geological events in the region.