The biggest mountain in the world

I have already talked about about the outpouring of molten lava from volcanoes to create new mountains, but when that outpouring happens on the ocean floor, then little by little the solidified lava will build up until it reaches the level of the sea, and a new island is formed.

In fact, all the islands in the Hawaiian archipelago have been formed in this way, by a 'hotspot' or weakness in the earth's crust.

The theory is that the tectonic plate beneath much of the Pacific Ocean moves in a northwesterly direction, the hot spot remains stationary, slowly creating new volcanoes. This explains why only volcanoes on the southern half of the islands are currently active.

The tallest volcano, Mauna Kea stands at 13,796 ft (4,205 m) and is taller than Mount Everest if followed to the base of the mountain—on the floor of the Pacific Ocean.