View over the youngest volcano of Greece - Néa Kaméni island!

Due to the subduction, which is due to the sinking of the African plate under the Euro-Asasian, massive rock masses north of Crete are melted and mixed with heavier magma of the earth's crust. This creates lighter magma that slowly rises in the cracks in the earth's crust. Where there are particularly many faults and cracks, the active volcanic areas of Greece have established in a round zone. The so-called "Aegean arch" begins in the west of Greece with the volcanic areas Loutraki, Sousaki, Methana, Aegina and Poros, then leads via Milos, Kimolos and Polyaegis to Santorini and ends at the islands of Cos and Nisyros. In this area, volcanic eruptions have occurred in historical times and there will also be new eruptions in the future. The potentially most dangerous volcano is that of Santorini with the last eruption in 1950.

Santorini's volcanism began about 2-6 million years ago with undersea eruptions that primarily produced pillow lava. It was only around 900,000 years ago that the first volcanoes slowly reached the surface of the water and formed the volcanoes on the Akrotiri peninsula (red beach, balos, kokkini Petra, etc.).

Then larger stratovolcanoes built up again and again, which were destroyed by later eruptions of newer volcanoes. Again and again there were larger craters that formed the first calderas. There were three devastating, large eruptions, each leaving thick layers of pumice. The last catastrophic eruption was around 1627 BC. BC, which also brought the Minoan culture into the crisis and climate change throughout Europe. The island in the middle of the caldera was destroyed during this time and new islands were only formed by new volcanic eruptions 900 years later.

97 BC Hiéra island first built up, followed by further volcanic eruptions that formed Paléa Kaméni, where AD 726. another massive eruption occurred, leaving the green crater lake behind. Then in 1540 Mikrí Kaméni was formed and slowly expanded to Néa Kaméni through further activity. The last outbreak occurred there in 1950. There was an earthquake crisis in 2011-2012 and the region was raised by up to 9 cm. New magma rose. Since then there has been silence. Time will tell whether this new magma chamber breaks out or simply cools down.

For about 14 days now, the earth has been shaking around the uninhabited island of Anhydros, located between the islands of Amorgos and Santorini. So far, approximately 2,000 earthquakes have been recorded, ranging in magnitude from 2.3 to 5.1 on the Richter scale. These tectonic quakes are caused by the subduction of the African Plate beneath the Eurasian and Anatolian Plates. The Aegean region is fragmented into multiple smaller plates that either collide or grind against each other at varying depths of the Earth's crust. Around Anhydros, one of these plates appears to be stuck and is now releasing with a series of earthquakes.

According to Greek seismologist Professor Gerasimos Papadopoulos, the current seismic activity is still in its early stages. He believes that the main earthquake may not have occurred yet and warns that magnitudes of 6 to 7 on the Richter scale are possible. While the island of Santorini has not been officially evacuated, thousands of residents have voluntarily fled to Athens via ferries and planes. There is no clear indication of when this earthquake crisis will subside—it could last for weeks or even months.

The greatest threat comes from potential tsunamis, which could impact the entire Aegean region, as well as the coasts of Turkey, Syria, and Israel. Authorities are warning people to stay away from coastal areas, or if near the sea, to remain highly vigilant for any sudden changes in water behavior.

So far, the underwater volcano Kolumbo, located northeast of Santorini, has not been directly affected by the earthquakes, and the Nea Kameni volcano remains quiet. However, since 2011, there has been noticeable uplift in the northern part of Santorini’s caldera, suggesting that magma is rising. Current observations indicate that the island of Santorini continues to experience uplift, but it remains uncertain when or if this process, in combination with tectonic activity, will lead to volcanic eruptions.

There is no immediate reason for panic, but precautionary measures should be taken. Authorities have begun setting up emergency shelters and increasing the number of monitoring instruments in the area.

The year 2025 is shaping up to be a geologically turbulent one for Greece—unfortunately, it may also be catastrophic for Greek tourism. And it is not only Santorini that is affected, but also all the surrounding islands in the region.

Since 2012 there are many signs of Santorini volcano waking up. Lots of small earthquakes show an uprising magma chamber and an uplift of 9 cm on some parts of the island. The last eruption took place in 1950 but since that time the volcano remains relatively calm. When or if there will be the next eruption - that is the question! But nobody knows the answer...

Here you can find a research about an important evacuation plan and about the local people and their knowledge about volcanic dangers:

LINK to PDF-Dokument (englisch).