How Volcanic Islands Form

Volcanic islands form when magma erupts from the ocean floor and accumulates over millions of years. Hawaii sits over a hotspot that has been creating islands for 70 million years. Iceland sits on the Mid-Atlantic Ridge where tectonic plates diverge.

Santorini formed from a catastrophic eruption around 1600 BC. Stromboli has erupted continuously for over 2,000 years. The Galapagos are relatively young at 3-5 million years..