earthquakeScientists in Japan studying earthquakes have detected a rare deep-Earth tremor, known as an S wave microseism, for the first time.

Published in US journal Science, the study from researchers Kiwamu Nishida and Ryota Takagi from the National Research Institute for Earth Science and Disaster Prevention in Japan announced scientists successfully detected not only P wave microseisms triggered by a severe and distant North Atlantic storm, known as a weather bomb, but also S wave microseisms, too.

S waves refer to secondary waves, which are slow and move only through rock, not liquid.