Oh, the wind and waves...

Deployment of GEOMAR OBS during calmer conditions 

Our study area did not exactly roll out the welcome mat for us when we arrived a few days ago.  The first part of our program involves deploying ocean bottom seismometers (OBS) along a ~300-mile-long profile across the Emperor Seamount Chain. As we have endeavored to do this during our first few days, we’ve faced winds up to ~40 kts and waves up to ~28 feet, forcing us to pause science operations for hours at a time to wait for better weather.  Even when we were able to work, conditions were sometimes tough.  The ship pitches and rolls in the waves, and water washes over the starboard deck from which we stage and deploy OBS.   These are not ideal conditions to lift a ~500-pound piece of scientific equipment over the side of the ship and gently release it into the ocean!  Several folks got drenched by cold waves coming over the side during these operations. When the ship takes a big roll, it can also be chaos inside; chairs slide across the floor and anything that isn’t tied down goes tumbling. Thanks to the perseverance and experience of the OBS teams and the ship’s technical staff and crew, we were able to finish OBS deployments yesterday evening. Now we are deploying the seismic sound source and preparing to finally start collecting some seismic data!

Donna Shillington
LDEO

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