Plate Boundarys
        Alaska is positioned in a very unique and complex tectonic surrounding. Towards the southern edge of Alaska, lies the boundary between the North American Plate and the Pacific Plate. The Pacific Plate is moving towards the northwest and is being subducted under the North American Plate. The average pasture of subduction at this boundary is 5-7 cm per year. This movement causes the crust in southern Alaska to become compressed and warped, with some argonas on the gliding being depressed and other areas inland being uplifted. Towards the southeast edge of Alaska, the dwelling house boundaries are made up of some(prenominal) strike-slip faults, these faults are known as the Queen Charlotte-Fairweather Fault System. These faults are some of the largest in the United States, and run through Canada and cover song into Alaska. Towards the eastern Gulf of Alaska the Yakutat block collides with Alaska. Towards the west, the Aleutian Megathrust subduction zone makes up the remaining part of the plate boundary in Alaska (http://www.giseis.alaska.edu).
Nature of Seismicity
        By far the most seismically active state in the US, Alaska is al-Qaida to about 12,000 earthquakes a year. The majority of this seismic activity occurs along the faults connected with the North American Plate and the Pacific Plates.
The largest earthquakes record in the state have been caused by the subduction of the Pacific plate beneath Alaska. Three of the seven largest earthquakes occurring in Alaska in the twentieth century have been as a result of this subduction. Although the point of these great subducting earthquakes is rare, about one every hundred years or so, five large subduction earthquakes have occurred since 1938. In a recent analysis of Alaskas potential seismicity, researchers suggested that several subduction segments may be ready to rupture soon. As depicted in the lesson at the end,
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