The islands of Fiji and Vanuatu rise from the tropical waters of the South Pacific in one of the most tectonically active and geologically complex regions of the world. A new study of volcanism in this area sheds light on the ancient breakup of a long island arc, which swung apart like "double saloon doors." Fiji and Vanuatu started out as close neighbors and ended up 800 miles apart on separate sections of what had once been a continuous arc.
