To take ‘ultrasound’ of sea floors
Oregon (USA), Feb 14: Fin whales have one of the loudest and strongest calls in the ocean. They can travel up 1600 kms and reach 189 decibels, as loud as the noise produced by a large ship. Previously, these whale calls were an
annoyance to seismologists (people who study earthquakes). Researchers used to place ball-shaped seismometers on the ocean floor to record earthquakes.
These instruments often captured the repetitive songs of fin whales. But, while analysing the whales’ songs’ echoes, they found that the songs passed through the ground of the sea floor and bounced back off the subsurface rocky layers. This helps in mapping the sea floor and creating an ultrasonic image of the Earth’s crust up to a depth of 3 kms under the ocean floor. This could help reveal details about earthquakes without disturbing sensitive marine life.
