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
Japanese occupation of the Andaman Islands for maintaining order. Japanese Army personnel in Andaman and Nicobar The events of the next three years are not easy to establish, as the Japanese destroyed all records when they left. The principal sources are an unpublished report by local resident Rama Krishna: "The Andaman Islands under Japanese Occupation 1942–5", another unpublished account by a British Officer, D. McCarthy: "The Andaman Interlude" (he was sent on a secret mission to the islands in 1944), together with the memories of the older inhabitants interviewed by historians. All these, and the published works that draw upon them, are in agreement that the