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
The Cook Inlet Basin The Cook Inlet Basin The Cook Inlet Basin is a northeast-trending collisional forearc basin that stretches from the Gulf of Alaska into South central Alaska, just east of the Matanuska Valley. It is located in the arc-trench gap between the Alaska-Aleutian Range batholith and contains roughly 80,000 cubic miles of sedimentary rocks. These sediments are mainly derived from Triassic, Jurassic and Cretaceous sediments. The region is heavily influenced by two major tectonic elements which are still active in the area today. The western side of the basin lies directly above the Aleutian subduction zone where the Pacific Plate is subducting