to explore the geologic structure below the ocean floor, seismic
airguns produce "explosions" of air at regular intervals.
This explosive release of air can create source amplitudes
up to 240dB. The PMEL autonomous hydrophone array deployed
in the central Atlantic Ocean
recorded at least three different airgun sources from around
the Atlantic Basin, sometimes simultaneously. The most frequent
origin locations were near Nova Scotia, Canada, Northeast
Brazil, and Northwest Africa. Airgun signals dominate approximately
75% of the annual data recordings.
for full-sized image.
recorded signal has been sped up 10 times)