Unspooling seismic streamer


Dan Sousa, LDEO, carrying a 'bird,' which is used
to control streamer depth. The streamer reel
is in the background.
Having finished the deployment of 70 OBS on the seafloor, we spent ~20 hours deploying the other key parts of the seismic gear for our project: a seismic “streamer” and a seismic source.  Seismic streamers are long cables filled with closely spaced hydrophones, which detect small pressure changes associated with passing sound waves.  The streamer for our program is ~10 miles long! It is stored on large reels, which unspool the streamer off the back of the ship and into the water. As we deploy the streamer into the ocean, we attach equipment to it that is used to control the depth of the streamer beneath the sea surface and determine its location behind the ship, which is very important for such a long cable.  The depth controllers have wings that can be pivoted to dive the streamer deeper or bring it shallower, so they are affectionately called 'birds.'

Now that we have 70 OBS on the seafloor and 15 km of seismic streamer behind the ship, it’s time to collect some data!

Donna Shillington, LDEO

Seismic streamer entering the ocean from the back of the ship.




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