May 28, 2021 05:31 AM EDT
Common Earthquakes
(Photo : Photo by Yuichi Yamazaki/Getty Images)
The majority of earthquakes happen within 70 kilometers of the Earth's surface. They occur when tension builds up at fault between two chunks of rock, forcing them to slide past each other unexpectedly.
Deep Earthquakes
(Photo : Photo from IFRC Europe)
However, deeper within the Earth, the tremendous pressures generate too much friction for this type of sliding to occur, and the high temperatures help rocks bend to adapt to shifting stresses. Since the 1920s, scientists have been able to identify earthquakes that originate more than 300 kilometers under the surface, despite the fact that it is logically unthinkable.