W.with a call as loud as a big ship, fin whales (Balaenoptera physalus) are among the loudest creatures in the sea. For some seismologists who monitor earthquakes by recording ocean floor vibrations, whale calls are a nuisance as the bat dampens their measurements. For two earthquake researchers, however, they found that reflections from whale vocalization could be helpful in measuring the structure of the ocean’s crust. Your results will appear today (February 12th) in science.
“It’s a fine example of how we use the data the planet provides for us,” says Jackie Caplan-Auerbach, a seismologist and volcanologist at Western Washington University who was not involved in the work The New York Times.
Seismological stations on the sea floor are used to monitor earthquakes and often record whale songs. Researchers have previously used these random records to track fin whale movements, but this marks the first time whale calls have been used to study the planet.
A seismological station that recorded a fin whale song accelerated ten times
Seismologists Václav Kuna from the Institute of Geophysics of the Czech Academy of Sciences in Prague and John Nábelek from Oregon State University analyzed six fin whale songs recorded with seismometers installed in the Pacific Ocean off the coast of Oregon. When whale calls hit the ocean floor, some of these sound waves are converted into seismic waves that move through the layers of the ocean’s crust. The waves eventually bounce back to the surface layer, where they are picked up by a seismometer. By measuring the time it took for the waves to reflect back, they could estimate the thickness of each layer of crust.
To study the ocean’s sediment structure, scientists previously relied on air guns, which create sound waves by blasting compressed air onto the sea floor. The noise from these devices can harm marine life. Kuna tells science This whale call analysis could offer a more environmentally friendly approach to studying ocean crust, especially in marine protected areas where air guns are banned. This method is unlikely to replace air rifle surveys entirely, as fin whale calls do not penetrate as deeply into the ocean crust and provide a less detailed picture of the ocean substrate. science Reports.