Pacific Ocean closed loop of the andesite line are most of the deep troughs, submerged volcanic mountains, and oceanic volcanic islands that characterize the Pacific basin. Here basaltic lavas gently flow out of rifts to build huge dome-shaped volcanic mountains whose eroded summits form island arcs, chains, and clusters. Outside the andesite line, volcanism is of the explosive type, and 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. The Pacific Ocean is the only ocean which is almost
Circum-Superior Belt pounds of nickel. At least two nickel deposits are in progress by Vale Inco at the Thompson and Birchtree mines. At least 70 million pounds of nickel has been mined since 2005. At the city of Thompson, nickel of the Thompson Belt is smelted and refined in facilities. This smelting and refining process contributes to about one-third of the total nickel output in Canada. In the Cape Smith Belt of northern Quebec, the Raglan Mine lies in copper-nickel deposits of the ultramafic Katiniq Suite sills. The Katiniq Suite sills are also within an area that is presently explored for nickel,