Geology of the Pacific Ocean Guinea, and New Zealand lie outside the andesite line. Outside of the andesite line, volcanism is explosive; the Pacific Ring of Fire is the world's foremost belt of explosive volcanism. The Ring of Fire is named after the several hundred active volcanoes that sit above the various subduction zones. In 2009, the deepest undersea eruption ever recorded occurred at the West Mata submarine volcano, a mile beneath the ocean, close to the Tonga-Kermadec Trench, within the Ring of Fire; it was filmed by the US Jason robotic submersible which descended over . The Pacific Ocean is the only ocean which
Philippines and the Spratly Islands are occupying and/or controlling ten features, (seven islands, three reefs): By comparison, within the Spratly Islands: Also, the Philippines has some features that are "virtually occupied". These are features that lie in very close proximity to Philippine-occupied features, and can be seen within the horizon. (A 15 meter-height vision gives about of horizon distance). These include: North Reef, Sandy Cay, Loaita Nan and Loaita Cay. Also, most features that lie to the east of the 116°E, though not necessarily occupied, are largely controlled by the Philippines. The Philippine assertion of sovereignty over the Spratly Islands began in May 1956, when