![\"Global](\"https:\/\/satdi.umh.es\/files\/2026\/04\/Mapa-global-de-sismos.jpg\")
<\/a>The map covers continental mantle earthquakes occurring around the world. Illustration: Axel Wang.<\/strong><\/p><\/div><\/p>\n <\/p>\n For decades, it was believed that earthquakes originated only in the Earth’s crust, but recent research has confirmed that they also occur in the mantle. A team led by Shih-Chi Wang of Stanford University has produced the first systematic global map of these deep earthquakes, identifying 459 events since 1990. Their findings reveal significant concentrations beneath the Himalayas and near the Bering Strait.<\/p>\n The key to understanding these phenomena lies in the Moho discontinuity, which separates the crust from the mantle. While most earthquakes occur at shallow depths, some originate more than 80 kilometres below the surface, outside subduction zones. Although their existence had long been suspected, their low frequency and the scarcity of data had made their confirmation difficult until now.<\/p>\n To distinguish them, the researchers developed a method based on the analysis of seismic waves, comparing the energy of Sn waves, which travel through the mantle, and Lg waves, which propagate through the crust. This approach made it possible to analyse more than 46,000 seismic records and establish a robust catalogue of continental mantle earthquakes.<\/p>\n Although these deep earthquakes rarely cause damage at the surface, their study may provide new insights into the Earth’s internal dynamics. Scientists believe that they could form part of an interconnected seismic system linking the crust and the mantle, and they hope that future research will help to better understand the mechanisms that trigger the most dangerous earthquakes.<\/p>\n