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 Japanese occupation of the Andaman Islands The Japanese occupation of the Andaman Islands occurred in 1942 during World War II. The Andaman and Nicobar Islands (8,293 km² on 139 islands), are a group of islands situated in the Bay of Bengal at about from Kolkata, from Chennai and from Cape Nargis in Burma. Until 1938 the British government used them as a penal colony for Indian and African political prisoners, who were mainly put in the notorious Cellular Jail in Port Blair, the biggest town (port) on the islands. Today they form a Union Territory of India. The only military