Description
The Santorini volcanic group is composed of three islands (Thera, Therasia, and Aspronisi), arranged around a flooded caldera, within which are the Palea and Nea Kameni Islands. These postdate caldera collapse (3.6ka) and are the subaerial expressions of an intracaldera, largely submarine lava shield (Druitt, 2014). Santorini has evolved over at least 650 ky; detailed mapping and chronological (K-Ar, 40Ar/39Ar) studies have revealed the following stages (Druitt et al. 1999; Fabbro et al., 2013):
• The early centers of Akrotiri peninsula (650-550ka) in the south, involving shallow marine to emergent activity, followed by about 200m of uplift (predominantly dacites and rhyodacites); cinder cones of the Akrotiri peninsula;
• Construction of the large Peristeria stratovolcano (550-450ka) in the north (andesitic stratocone complex);
• Products of the first explosive cycle (pyroclastic eruptions and minor shield formation);
• Products of the second explosive cycle (pyroclastic eruptions and formation of the Simandiri, Skaros and Therasia shields);
• The Kameni shield;
Sandy beach is located in the southern part of Santorini caldera, between Cape Aspronis and Cape Loumavari. The model has an extent of 420×250 m and a height of 91m. To the east, it is composed of andesitic and basaltic cinder cones of the Akrotiri peninsula with subordinate agglutinate and lava. To the west, it is composed, in the upper part, of Cape Riva Tuff (rhyodacitic plinian pumice), a small part of upper scoriae 2 (andesitic pyroclastic deposits) and, close to the beach, of middle tuffs (andesitic to dacitic pyroclastic deposits), all volcanic products of the second explosive cycle.
Credits: UAV-based survey and 3D DOM by Fabio L. Bonali; funding is from MIUR project ACPR15T4_00098 (http://argo3d.unimib.it/). The volcanic products have been analyzed by Paraskevi Nomikou.

Credits: UAV-based survey and 3D DOM by Fabio L. Bonali; funding is from MIUR project ACPR15T4_00098 (http://argo3d.unimib.it/). The volcanic products have been analyzed by Paraskevi Nomikou.

References

  • Druitt, T. H, Edwards L., Mellors R.M., Pyle D.M, Sparks R.S.J., Lanphere M., Davies M., & Barreirio, B. (1999). Santorini volcano,Geological Society Memoir. J. Geol. Soc.Lond. 19, 165.
  • Druitt, T. H. (2014). New insights into the initiation and venting of the Bronze-Age eruption of Santorini (Greece), from component analysis, Bull. Volcanol., 76, 794.
  • Fabbro, G., Druitt, T.H., Scaillet, S., (2013). Evolution of the crustal magma plumbing system during the build-up to the 22-ka caldera-forming eruption of Santorini (Greece), Bull Volcanol 75, 767.