Ενεργά και ανενεργά ηφαίστεια της Ελλάδος

Volcanoes, harmful phenomenon or source of wealth? In any case, are linked to Earth’s interior, where fluid rocks give the form of lava.

There are quite a few myths that accompany the existence of volcanoes, interpreting the manifestation of volcanic and seismic activity and attributing it to Hephaestus. Hephaestus, god of fire and metallurgy is said to have used the volcano as the base of his forge. As an excellent craftsman he crafted weapons for heroes, demigods and gods at the age of antiquity highlighting the superiority of their owners in epic battles.

Other versions of the myth claim the forge of Hephaestus to be hosted in other volcanic regions, such as Etna or Vesuvius.

As strange as it may seem, both lava and ash erupting from volcanoes, as well as the rocks which eject, are materials quite beneficial to mankind. Most lavas are a source of excellent building materials and various metals in large quantities, which people can use.

In this article, active and inactive volcanoes of Greece are presented, whose history fascinates to this very day.

Kos

The volcanic eruption of Kos was a geological event of the Pleistocene Epoch. The eruption that took place 160,000 years ago was the largest that has occurred in the southeastern Mediterranean in the last 2,000,000 years and one of the most violent eruptions in the world, surpassing by far even that of Santorini.

The ancient volcano became silent after that fierce explosion and over time was covered by sediments tens of meters thick. Many millennia later, another underwater crater was created in its place, which was called “Abyss”, continuing to be active, but without posing a danger to the surrounding islands.

When the explosion took place, Kos consisted of two separate islands (Kefalos and Dikaios) and in the sea area between Kos and Tilos there was no other island, as all the surrounding islands (Nisyros, Giali, Pergousa, Pachia and Strongyli) they were created by volcanic activity at a later stage. The pyroclastic materials that were ejected “united” Kefalos and Dikaios, giving Kos the shape it acquires today.

Methana

The Methana volcano belongs to the volcanic arc of the southern Aegean, is located at its western end and has significant geothermal potential, nevertheless not fully explored. It had intense volcanic activity between the period 276 to 239 BC, from reports by the ancient historians Strabo, Pausanias and Ovid.

The Methane volcano lists thirty craters. The most well-known crater of this volcano is situated to the northwest, above the village of Kameni Chora and is no longer active. The crater of Kameni Chora is about 50m deep, 100m in diameter and the highest height of the cone is 425m. On its north-eastern side, two other – parasitic – craters can be seen.

Milos

Milos is first and foremost a volcanic island (like the neighboring islands of Kimolos, Polyaigos, Antimilos, Glaronisia, etc.). The island was created by volcanic activity that commenced 2-3 million years ago and seized 90,000 years ago. This volcanic activity occurred on land and sea, with the result that fossilized shells can be found in the rocks on the island. Although there have been no recent eruptions, the island is dangerous, since in addition to the earthquakes associated with the volcanic activity, there have been phreatic eruptions with local disasters. The most recent of these occurred between 1st and 3rd AD. century in the area of Agia Kyriaki.

There are two extinct volcanoes on the island, the volcano of Phyriplaka in the central southern part of the island, which has an impressive crater with a diameter of 1700 meters and a height of about 220 meters, and the volcano of Trachilas in the northwest. In addition, on the island there are many volcanic roads, such as the castle of the country, and the highest peak of the island, Prophet Ilias. Consisting of lava that solidified before being poured, it is mainly andesite. The volcanic rocks at Sarakiniko are white in color and were created by the deposition of repeated layers of material. Fossils have been found inside them.

Nisyros

Nisyros is the newest of the major volcanic centers of Greece and is included along with Methana, Milos and Santorini among the active volcanoes of our country. The oldest rocks are 160,000 years old, while the youngest (prehistoric) are 15,000 years old, covering the entire island.

It is the youngest active, large volcano of the Aegean, with a wonderfully preserved caldera 4 km in diameter.

Largest part of Nisyros island is mountainous, volcanic and very fertile. It consists of volcanic rocks, with outcrops of volumes created by old volcanic actions. The different types of rocks (basalts, andesites, dacites, rhyolites, etc.) have been used for the construction of various buildings such as the Paleokastro and the Bell Tower of Ag. John the Theologian outside Nikia.

The most recent powerful eruption was in 1888 which formed a cylindrical conduit of volcanic material at least 25 meters in diameter.

Kolumbos

Kolumbos or Kolumbo is an active submarine volcano located 6.5 kilometers northeast of Santorini, which belongs to the Volcanic Arc of the South Aegean. It became known after a large volcanic eruption on September 27, 1650.

Its crater is about 3 kilometers in diameter and 512 meters deep. In a large area around the volcano, hydrothermal wells have been identified from which hot water, up to 220°C, with dissolved minerals harbouring a rare ecosystem of filamentous bacteria, gushing out.

During this activity, approximately 70 people and a large number of domestic animals died, mainly due to the poisonous gases that were emitted for months from the volcano.

Many opinions have been expressed about the origin of the word, with the dominant one wanting originating from the Italian colombo meaning dove, owing to at the time of the eruption in 1650 on the surface of the sea, white foams shaped like a dove were monitored.

Nea Kameni

Nea Kameni or formerly also Nea Kaimeni, “the volcano” for the locals, is a volcanic island in the center of the Santorini caldera, which began to be shaped in 1570 (or 1573), with the initial creation of Mikri Kameni and is the most recent piece of land in the Mediterranean Sea. [1] Its area today is 340 hectares and its highest point is 127 meters above sea level. There are two anchorages on the island, Taxiarchis bay, in the southeast of the island, and Erinia bay in the north.

It is a monument of major scientific interest and has been designated by the Ministry of of Culture as “a place of historical and outstanding natural beauty”. It is an active volcanic center, with the oldest rocks being 430 years old and the youngest only 50 years old. The island is a daily attraction for hundreds of tourists who arrive at the island’s bay from the Old Port of Fira and who are guided around the island’s craters.

Gyali

Among Kos and Nisyros, at a distance of about 4 nautical miles from the latter, there is a volcanic islet with an area of only 4.6 square kilometers. It is called Gyali, it belongs to the Dodecanese but few people know of its existence. The longest distance on the island does not exceed 5 km, its widest is about 2.1 km and the smallest is just under 500 m.

At the region between Kos and Nisyros, and specifically around the islet of Gyali, there are several underwater volcanoes. Scientists claim that the first volcanic events in the area took place 2.5 million years ago, while 160,000 years ago a huge volcanic eruption occurred near Voreio Gyali, due to which it seems that western Kos, Nisyros and the smaller islands were created – its satellites: Pergousa, Pachia, Strogyli and Gyali.

Until then, Gyali and Strogyli did not exist, while Nisyros was an underwater volcano with only its top projecting slightly above the sea surface. Nowadays, the volcano of Gyali, which is about 7 km away from the volcano of Nisyros, is no longer active.

Gyali has been declared a Landscape of Outstanding Natural Beauty.