Bonin Islands Pacific Plate is subducting under the Philippine Sea Plate, which creates an oceanic trench to the east of the islands: the Bonin Trench. The crust of the Ogasawara Islands was formed by volcanic activity when subduction began 45–50 million years ago, and is composed mostly of an andesitic volcanic rock called boninite, which is rich in magnesium oxide, chromium, and silicon dioxide. The Ogasawara Islands may represent the exposed parts of an ophiolite that has not yet been emplaced on oceanic crust. The rocks of the Volcano Islands are much younger; Iwo Jima is a dormant volcano characterized by rapid
Music of the Northern Mariana Islands Music of the Northern Mariana Islands The music of the Northern Mariana Islands is dominated by the folk music of the Chamorros, which remains an important part of the islands' culture, though elements of music left by American, German, Spanish and Japanese colonizers are also in evidence. There are both Carolinian and Chamorro traditional chant styles. A variant of the Spanish cha-cha-chá is popular, as is a Carolinian "stick dance" which combines improvised percussion and foot stomping. A well-known stick dance group is the Talabwog Men Stick Dancers. The national anthem of the Northern Mariana Islands is "Gi Talo Gi