'Weather Bomb' in Japan Reveals Earth's Geological Secrets
A team of scientists in Japan detected a rare form of an earthquake on the ocean floor. However, the tremors felt are reportedly not an earthquake but a rare phenomenon called "weather bomb." This phenomenon has helped scientists in identifying details about the earth's interior, the mantle and crust.
According to the American Association for the Advancement of Science, microseisms are indistinct earthquake tremors commonly caused by "the sloshing of the ocean's waves on the solid Earth floor during storms."
There are two kinds namely P-wave microseisms, which animals can detect before an actual earthquake and which have already been charted, and S-wave microseisms, which humans can detect during an earthquake. S-waves are particularly hard to chart. Yet, despite the difficulties in charting both types, scientists study the microseisms in hopes of unlocking information about the earth's mantle and crust.
However, a new report led by Japanese professors Kiwamu Nishida and Ryota Takagi of the University of Tokyo manage to document and detect both types of microseisms. In their study which was published in the journal Science, the professors explain how they managed to detect both P- and S-wave microseisms. Researchers attributed their success to the discovery of a "weather bomb," which occurred in the North Atlantic Ocean back in 2014.
"This is where severe oceanic storms can help," states the study. "Atmospheric pressure can drop rapidly during these events, generating oceanic waves so strong that a small fraction of their energy makes it all the way down to the sea floor and generates faint P-waves and S-waves in the rocks - as if a very weak earthquake has occurred."
Through recording the P- and S-waves, Professor Takagi and Professor Nishida were able to capture a high-resolution image of the Earth's internal structure below the rare phenomena, the weather bomb. This would not only greatly aid in understanding the interiors of the earth, but aid in detecting oceanic storms and earthquakes.
"We're potentially getting a suite of new seismic source locations that can be used to investigate the interior of the Earth," explains Peter Bromirski, the geophysical oceanographer at the Scripps Institution of Oceanography in California.
The discovery of S-waves thanks to the "weather bomb" will help scientists in uncovering earth's geological secrets.