Surtsey is an island off SW Iceland, it was formed by volcanic eruptions beginning in November of 1963 and ending in June 1967. No further eruptions are expected there. The volcano is a composite form, where lava has covered the existing cinder cone and formed erosion-resistant rock. Although half of the original island is again covered by water, the island and its associated undersea ridges should survive for a long time. Several other islands in the archipelago formed in the same way over the last few centuries.