Santorini is basically what stays after a colossal volcanic emission that crushed the most punctual settlements on an once in the past single island, and made the current geographical caldera. A goliath focal, rectangular tidal pond, which measures around 12 by 7 km (7.5 by 4.3 mi), is encompassed by 300 m (980 ft) high, soak bluffs on three sides.The principle island inclines descending to the Aegean Sea. On the fourth side, the tidal pond is isolated from the ocean by another considerably littler island called Therasia; the tidal pond is associated with the ocean in two spots, in the northwest and southwest. The profundity of the caldera, at 400m, makes it unimaginable for any however the biggest boats to grapple anyplace in the secured inlet; there is additionally an angler's harbor at Vlychada, on the southwestern drift. The island's essential port is Athinios. The capital, Fira, sticks to the highest point of the bluff looking down on the tidal pond. The volcanic rocks introduce from the earlier emissions include olivine, and have a little nearness of hornblende.
It is the most dynamic volcanic focus in the South Aegean Volcanic Arc, however what remains today is mainly a water-filled caldera. The volcanic bend is around 500 km (310 mi) long and 20 to 40 km (12 to 25 mi) wide. The district initially turned out to be volcanically dynamic around 3– 4 million years prior, however volcanism on Thera started around 2 million years back with the expulsion of dacitic magmas from vents around the Akrotiri.
The island is the site of one of the biggest volcanic ejections in written history: the Minoan emission (here and there called the Thera emission), which happened nearly 3,600 years back at the tallness of the Minoan civilization.The emission left a substantial caldera encompassed by volcanic fiery debris stores many meters down. This may have driven in a roundabout way to the crumple of the Minoan progress on the island of Crete, 110 km (68 mi) toward the south, through a monstrous tidal wave. Another well known hypothesis holds that the Thera emission is the wellspring of the legend of Atlantis.