Dean Livelybrooks here, blogging in English
GREETINGS, ¡HOLA, BON JOUR, HALLO
I’m writing from the computer lab in the Research Vessel Atlantis. We are at sea in the Pacific. This is our offical blog. Among us there are English, Spanish, French and German speakers, and we will identify our language as we post. There are 22 of us among the science crew on this cruise.
The clock just turned over to day 3 on the Atlantis. To date we’ve recovered 3 ocean-bottom seismometers (OBSs) that have sat on the ocean floor off the coast of northern California, Oregon and Washington for the past year. Our job on this cruise, leg 3 of the Cascadia Initiative is to recover the remaining 30 of the 70 OBSs deployed last year. The next 3 cruises this summer will re-deploy those OBSs in the northern part of Cascadia to record until next year.
What’s “Cascadia” you may ask. Its bounded by a spreading center on the west, a place where brand-new Earth’s crust is made and moves towards the coast. To the east are the volcanoes created by this ‘oceanic plate’ moving below (or ‘subducting’) the less dense North American plate that people in the U.S., Canada, and part of Mexico live on. Why study Cascadia? It is known to have very large earthquakes, just like recent ones in Japan and Sumatra. And just like in those places, Cascadian earthquakes (scientists call them ‘megathrust events’) can cause large tsunamis.
So we place seismometers and pressure gauges on the ocean floor to study Cascadia, with an eye towards improving our understanding of what could happen during the next big ‘megathrust event.’