Pacific Ocean width at about 5°N latitude, where it stretches approximately from Indonesia to the coast of Colombia—halfway around the world, and more than five times the diameter of the Moon. The lowest known point on Earth—the Mariana Trench—lies below sea level. Its average depth is , putting the total water volume at roughly . Due to the effects of plate tectonics, the Pacific Ocean is currently shrinking by roughly per year on three sides, roughly averaging a year. By contrast, the Atlantic Ocean is increasing in size. Along the Pacific Ocean's irregular western margins lie many seas, the largest of which
Geography of the Philippines of mountain ranges in this region is called "Zamboanga Cordilleras", with the highest elevation at Mount Dapi, which is high. The southern coastline is irregular, featuring two smaller peninsulas, the Sibuguey and Baganian, extending southward to the Moro Gulf. To the north of the Diwata Mountains at northeast Mindanao lie Siargao island and the Dinagat group of islands. Southwest of the Zamboanga Peninsula is the Sulu Archipelago, a chain of islands which comprise the smaller archipelago provinces of Basilan, Sulu, and Tawi-Tawi. The Philippines is divided into a hierarchy of local government units (LGUs) with the 81 provinces and 38