Examples of individual volcanic islands are Tristan da Cunha , Jan Mayen , Stromboli or Heard Island . Often only the remains of former volcanoes protrude steeply from the ocean, such as Ball's Pyramid , Sōfugan , Roca Partida or the Rocas Alijos . The world's largest volcanic island is Iceland .
Three different forms of volcanism are responsible for the formation of volcanic islands: individual hotspots , the activity of a mid-ocean ridge or a subduction zone . The first category includes the Azores, the Galapagos Islands and the Hawaiian Archipelago , the second category the Revillagigedo Archipelago off the west coast of Mexico with the islands of Socorro and San Benedicto, and the latter category includes the Aleutians, the Marianas and the Lipari Islands Islands . A special feature is the very large volcanic island of Iceland, where hotspot volcanism coincides with the volcanism of a mid-ocean ridge.