Measuring Active Tectonic and Volcanic Activity in Alaska

Abstract:

Alaska is one of the most tectonically active areas in the world, hosting a combination of subduction, arc volcanism, and large-scale deformation of the continental lithosphere. Most of the crust in Alaska and the surrounding area is moving relative to the North American plate, and the location of the edge of the geologically stable North American continent in the region is not yet clearly defined. Even the Arctic coast of Alaska appears to move relative to the North American plate, although quite slowly. Typical permanent crustal motions are of the order of a few to several mm/yr, and GPS observations across the region define a broad plate boundary zone that comprises not only Alaska, but also most or all of the Pacific coast of Canada. Active volcanism along the Aleutian arc also causes substantial surface deformation, as does the changing snow and ice load on the surface. Modern space geodetic data, mainly GPS but also including other systems, have allowed us to study a wide variety of problems in earth sciences in one single area.