Alpha Ridge Island is interpreted to represent the cratonward extension of the Alpha Ridge. The Alpha Ridge is part of the High Arctic Large Igneous Province. Alpha Ridge The Alpha Ridge is a major volcanic ridge under the Arctic Ocean between the Canada Basin (off Ellesmere Island) and the Lomonosov Ridge. It was active during the formation of the Amerasian Basin. It was discovered in 1963. The highest elevation is about 2,700 m over the ocean floor. It is 200 to 450 km wide. The Alpha Ridge, Lomonosov Ridge, and Nansen-Gakkel Ridge are the three major ranges that divide the Arctic Ocean
Geology of the Pacific Ocean as the Aleutian Arc off Alaska and the Kermadec-Tonga Subduction Zone north of New Zealand. As a result of the collision of the Nazca Plate and the South American Plate, the Andes Mountains emerged in western South America, close to the Peru–Chile Trench. Many large fracture zones aligned in an east-west direction, occur in the floor of the northeastern Pacific. The Pacific is a broad ocean basin (unlike the narrow Atlantic Ocean) and extends over a width of between New Guinea and Peru. The andesite line, a zone of intense volcanic and seismic activity, is a major regional distinction in