Something hidden deep underground supercharged this Chile earthquake

A powerful 7.4-magnitude earthquake struck northern Chile in July 2024—and it wasn’t supposed to be that strong. Unlike Chile’s infamous shallow “megathrust” quakes, this one ruptured deep inside the Earth, where shaking is usually weaker at the surface. Researchers discovered that the quake broke long-held assumptions by tearing through hotter rock layers than expected, fueled by a rare chain reaction that accelerated the rupture.