Case study: Surtsey

Surtsey video

Iceland is cut through by the mid-Atlantic ridge, a divergent plate boundary that has formed a massive mountain range across the centre of the Atlantic Ocean.

As the plates spread, magma rises up from the mantle below and escapes onto the seabed as lava. The lava cools quickly and solidifies in the cold sea water.

In 1963, powerful underwater eruptions led to the birth of a new island off the coast of Iceland, called Surtsey. As lava erupted onto the seafloor it solidified, eventually formed an island that emerged out of the water.