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
Nias Basin Nias Basin The Nias Basin (also known as the West Sumatra or Sibolga Basin) is a Forearc basin located off the western coast of Sumatra, Indonesia, in the Indian Ocean. The name is derived from the island that bounds its western edge, the island of Nias. The Nias Basin, the island of Nias (which is a subaerial part of the accretionary complex), and the offshore, submarine accretionary complex, together form a Forearc region on the Sunda Plate/Indo-Australian Plate collisional/subduction boundary. The Forearc region is the area between an oceanic trench and its associated volcanic arc. The oceanic trench associated with