Scientists detect rare, deep-Earth tremor in Japan

  • Scientists detect rare, deep-Earth tremor on the ocean floor in Japan
  • This is the first time this type of wave has been detected by scientists
  • Its location was traced to a distant and powerful storm between Greenland and Iceland
  • Findings could improve the early detection of earthquakes

For the first time, a rare deep-Earth tremor has been detected on the ocean floor in Japan.

With the use of seismic equipment in 200 sites on both land and on the seafloor in Japan, its location was traced to a distant and powerful storm between Greenland and Iceland, an article written by Shivali Best which was published on The Daily Mail mentioned.

Scientists said the findings could help experts learn more about the Earth’s inner structure which will then improve the detection of earthquakes and oceanic storms.

As noted by the scientists, the storm in the North Atlantic was known as a “weather bomb.”

Characterized by an intense low pressure system, a weather bomb has a central pressure that falls 24 millibars in a 24-hour period.

A weather bomb is a small but potent storm in which pressure quickly builds, creating a more vigorous storm.

The scientists explained that as the storm hit, groups of waves pounded the ocean floor between Greenland and Iceland and their readings showed that they were secondary (S) wave microseisms – or very faint tremors.

Unlike primary (P) waves, which are usually detected during major hurricanes, S waves are slow in motion and only move through rock.

S-waves, secondary waves, or shear waves (sometimes called an elastic S-wave) are a type of elastic wave and are one of the two main types of elastic body waves.

On the other hand, P-waves are a type of body wave, called seismic waves in seismology, that travel through a continuum and are the first waves from an earthquake to arrive at a seismograph.