Our planet’s greatest geological hazards are concentrated in its subduction zones, the places where two of Earth’s tectonic plates converge and collide. All the known earthquakes with magnitudes of 8.8 and higher have taken place at subduction zones, along with the most devastating tsunamis.

Research has shown that, in the past, the Cascadia subduction zone fault system, off the west coast of the United States and British Columbia, Canada, has produced many earthquakes with magnitudes up to 9.0 or greater, spawning tsunamis so large that they have caused damage across the Pacific in Japan.

Cascadia Offshore Subduction Zone Observatory (COSZO)

The offshore region where earthquake slip on the Cascadia fault is expected to occur is largely devoid of geohazard sensing instruments. COSZO is an infrastructure implementation project that will add a suite of geophysical sensors to the Ocean Observatories Initiative (OOI) Regional Cabled Array (RCA), off the coast of near Newport, Oregon, to create a seafloor observatory on the Cascadia subduction zone.

Early Warning Offshore Cascadia

To help improve our early warning capabilities for offshore earthquakes and tsunamis and improve our capabilities to monitor the Cascadia subduction zone, we are exploring the design and cost-benefit of an offshore real-time network extending along the full length of the subduction zone. Support for this effort has been provided by the Gordon and Betty Moore Foundation.

Cascadia Region Earthquake Science Center (CRESCENT) Offshore Observations Special Interest Group (SIG)

Enhancing the quality and quantity of offshore geophysical observations in Cascadia is critical to long-term efforts of advancing CRESCENT science goals and estimating the seismic hazard. The Offshore Observations SIG gathers broad community input on observational needs and priorities and identifies specific areas for accelerated progress through coordination and the development of collaborations that link the academic community, federal agencies, private companies, and international partners.