The Birth of a Caldera
Santorini, as we know it today, is the result of one of the most massive natural disasters in human history. Before the great eruption, Santorini was a round, mountainous island called Strongyli (the Round) — a thriving trade center of the Minoan civilization with the prosperous city of Akrotiri on the southern coast.
The Minoan Eruption (ca. 1600 BC)
Then came the catastrophe. The Minoan eruption (also known as the Thera eruption) was one of the strongest volcanic eruptions of the last 10,000 years — classified as VEI 7 (Volcanic Explosivity Index), comparable to the Tambora eruption of 1815, which caused the "Year Without a Summer." The eruption occurred in four phases:
- Phase 1: Pumice rain — a cloud of pumice and ash shot up to 36 km into the stratosphere and covered the island with up to 5 meters of pumice.
- Phase 2: Pyroclastic flows — glowing avalanches of gas, ash, and rock raced down the slopes and over the sea at up to 200 km/h.
- Phase 3: The collapse — the emptied magma chamber collapsed, and the center of the island caved in. The sea rushed into the crater, generating massive tsunamis that rolled as far as Crete, Egypt, and possibly the Greek mainland.
- Phase 4: What remained was the present-day crescent-shaped island — the rim of the collapsed volcano, the caldera.
The consequences were global: The ash rain darkened the sky, crop failures followed, and the Minoan civilization on Crete — Europe's first advanced culture — was so weakened that it was soon taken over by the Mycenaeans. The eruption might also have inspired the biblical plagues of Egypt and the myth of Atlantis (as conveyed by Plato) — a lost advanced culture on an island that sank into the sea.
