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USGS-NOAA cruise maps Cascadia subduction zone to assess earthquake hazards
From July 31 to August 23, a joint USGS-NOAA cruise mapped seafloor depths, texture, and gas seeps in the Cascadia subduction zone offshore of Washington, Oregon, and northern California.
From July 31 to August 23, a joint USGS-NOAA cruise mapped seafloor depths, texture, and gas seeps in the Cascadia subduction zone offshore of Washington, Oregon, and northern California. The largest earthquakes in the world occur within subduction zones along the giant fault between the down-going and overriding plates. Such earthquakes have potential to trigger large tsunamis by raising or lowering parts of the seafloor. During the cruise, scientists mapped a total of 6,452 square kilometers of seafloor. They identified new faults offsetting the seabed, possible mud volcanoes, and numerous seeps that highlight the region’s geologic activity. Results from this mapping and related efforts will provide key baseline information for assessing earthquake, tsunami, and landslide hazards and developing situational-awareness products, as part of USGS work on Reducing Risk where Tectonic Plates Collide.