Fin’s whale song – one of the strongest animal calls in the ocean – can be used as a seismic source for studying the structure of the Earth’s crust at the seabed, researchers report. Although the modern method produces results with a lower resolution compared to the high-energy airgun signals typically used in seismic ocean studies, the numerous whale calls could be the addition and development of seismic studies where conventional methods cannot be used are available worldwide. Study of the structure of oceanic crust often requires powerful seismic waves. This is usually done using boat-based air guns, which generate high-decibel explosive blows. Although effective, these explosions are among the loudest noises made by people in the ocean and have the potential to damage ocean life. However, whale songs, which can be as tall as large vessels and last for hours, appear at known frequencies to travel well through the ocean floor, and to they are often captured by the seismometer stations at the bottom of the ocean (OBS) that are used to record and monitor earthquake activity. Here, Václav Kuna and John Nábelek show not only that OBS recordings capture the songs of the whales but, that the powerful sound waves that these songs bring back and moving through the rock layers below the station. Kuna and Nábelek analyzed a total of six whale songs recorded by OBS stations off the coast of Oregon and found that they were able to use the signals to determine the thickness and seismic velocity of ocean sediment. and limiting the basalt floor, as well as the P-wave velocity of the lower crust below the stations. “Overall, our study shows that animal calls are useful not only for studying the animals themselves but also for studying the environment in which they live, “the authors wrote.
For reporters interested in trends, February 2020 Review in Science it has addressed the changing landscape of today’s oceans affecting marine life around the world. https: /
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