Santorini caldera
Santorini Caldera | |
---|---|
Highest point | |
Elevation | 367 m (1,204 ft) |
Coordinates | 36°23′44″N 25°27′33″E / 36.39556°N 25.45917°E |
Geography | |
Location | Aegean Sea, Greece |
Geology | |
Mountain type | Caldera (active) |
Last eruption | January to February 1950 |
Santorini caldera is a large, mostly submerged
Geography
The caldera measures about 12 by 7 km (7.5 by 4.3 mi), with 300 m (980 ft) high steep cliffs on three sides.
There are two small volcanic islands at the center of the caldera, Nea ("New") Kameni and Palea ("Old") Kameni.
The main island, Santorini has an area of 75.8 km2 (29.3 sq mi), Therasia 9.3 km2 (3.6 sq mi), and the uninhabited islands of Nea Kameni 3.4 km2 (1.3 sq mi), Palea Kameni 0.5 km2 (0.19 sq mi) and Aspronisi 0.1 km2 (0.039 sq mi).
Santorini's high walls, draped by whitewashed villages, combined with a sunny climate and good observation conditions, have made it a magnet for volcanologists,[1] as well as a highlight of tourism in the Aegean.
Geology
The volcanic complex of Santorini is the most active part of the
Non-volcanic rocks are exposed on Santorini at
The Kameni islands at the center of the caldera are made of lava rocks.
Volcanology
The caldera of Santorini lies in the center of the Christiana-Santorini-Kolumbo volcanic field, which comprises the extinct Christiana Volcano, the Santorini Caldera, the polygenetic submarine Kolumbo Volcano, as well as the Kolumbo Volcanic Chain.[4] This volcanic lineament evolved during four main phases of volcanic activity, which initiated in the Pliocene from several local centers that only recently matured to form the vast Santorini edifice. The present-day caldera is composed of overlapping shield volcanoes, cut by at least four partially overlapping calderas, of which the oldest southern caldera was formed about 180,000 years before the present era (BP). The subsequent Skaros caldera was created about 70,000 years BP, and the Cape Riva caldera about 21,000 years BP. The current caldera was formed about 3600 years BP during the Minoan eruption.[5]
Palea Kameni and Nea Kameni were formed as a result of multiple, initially submarine, smaller eruptions at the center of the caldera.[6]
Although dormant, Santorini is an active volcano. Numerous minor and medium-sized, mainly effusive, eruptions have built the dark-colored lava shields of Nea and Palea Kameni inside the caldera.
Their last eruption was in 1950, and now only
The huge
Eruptive history
Following is a list of the major eruptive events of Santorini beginning with the catastrophic Minoan eruption, as noted by the
Start date | Stop date | Characteristics of eruption |
---|---|---|
1610 BC ± 14 years ("Minoan eruption") |
Unknown | Central vent eruption, regional megatsunamis , caldera collapse, fatalities, mass evacuation.
|
197 BC | Unknown | Central vent eruption, regional fissure eruption, submarine eruption, new island formation, explosive eruption. |
Dec 31, 46 AD | Feb 1, 47 AD ± 30 days | Central vent eruption, regional fissure eruption, submarine eruption, new island formation, explosive eruption, lava flows, lava dome extrusion, tsunami. |
Jul 15 726 AD ± 45 days | Unknown | Central vent eruption, regional fissure eruption, submarine eruption, new island formation, explosive eruption, lava flows, lava dome extrusion, damage. |
1570 | 1573 | Central vent eruption, regional fissure eruption, submarine eruption, new island formation, explosive eruption, lava flows, lava dome extrusion. |
Sep. 27, 1650 | Dec. 6, 1650 | Flank (excentric) vent, regional fissure eruption, submarine eruption, new island formation, explosive eruption, lava flows, fatalities, damage, tsunami. |
May 23, 1707 | Sep. 14, 1711 | Central vent eruption, regional fissure eruption, submarine eruption, new island formation, explosive eruption, lava flows, lava dome extrusion, damage. |
Jan. 26, 1866 | Oct. 15, 1870 | Central vent eruption, regional fissure eruption, submarine eruption, new island formation, explosive eruption, lava flows, lava dome extrusion, fatalities, damage, evacuation. |
Aug. 11, 1925 | Mar. 17, 1928 | Central vent eruption, regional fissure eruption, explosive eruption, phreatic explosions, lava flows, lava dome extrusion. |
Aug. 20, 1939 | Jul. 2, 1941 ± 1 day | Central vent eruption, regional fissure eruption, submarine eruption, explosive eruption, phreatic explosions, lava flows, lava dome extrusion, damage. |
Jan. 10, 1950 | Feb. 2, 1950 | Central vent eruption, regional fissure eruption, submarine eruption, explosive eruption, phreatic explosions, lava flows, lava dome extrusion. |
IUGS geological heritage site
In respect of it being 'one of the largest calderas in the Mediterranean Sea formed by Plinian eruptions in a volcanic arc tectonic framework', the International Union of Geological Sciences (IUGS) included 'The Quaternary Santorini Caldera' in its assemblage of 100 'geological heritage sites' around the world in a listing published in October 2022. The organisation defines an IUGS Geological Heritage Site as 'a key place with geological elements and/or processes of international scientific relevance, used as a reference, and/or with a substantial contribution to the development of geological sciences through history.'[10]
References
- ^ a b "Introduction – Santorini Volcano". Retrieved 2011-04-19.
- ^ "Tectonic setting of Santorini". Retrieved 2011-04-20.
- ^ "Geology of Santorini – The prevolcanic basement". Retrieved 2011-04-20.
- ^ J. Preine, J. Karstens, C. Hübscher, P. Nomikou, F. Schmid, G.J. Crutchley, T.H. Druitt and D. Papanikolaou "Spatio-temporal evolution of the Christiana-Santorini-Kolumbo volcanic field, Aegean Sea", doi=https://doi.org/10.1130/G49167.1
- ^ a b "Santorini". Global Volcanism Program. Smithsonian Institution. Retrieved 2021-06-29.
- ^ "Santorini Volcanic Caldera, Greece". Retrieved 2011-04-19.
- ^ NBC News "Volcano on scenic Greek island getting a little restless 3 March 2012
- S2CID 128708746.
- ^ "Large Volcano Explocivity Index". Countries of the World. Archived from the original on 2020-09-30. Retrieved 2021-04-17.
- ^ "The First 100 IUGS Geological Heritage Sites" (PDF). IUGS International Commission on Geoheritage. IUGS. Retrieved 13 November 2022.