In a groundbreaking scientific achievement and a mile stone, researchers have captured “slow-motion” earthquakes happening in real time a major step forward in understanding and predicting powerful earthquakes and tsunamis.
These rare events, known as slow slip earthquakes (SSEs), release underground pressure not in minutes like typical quakes, but slowly over days or even weeks. Though they’re too gentle to be felt or cause immediate damage, they play a critical role in either releasing or building up stress along fault lines.
A research team from the University of Texas Institute for Geophysics (UTIG) successfully monitored two such events one in 2015 and another in 2020 using deep sea borehole sensors near Japan’s Nankai Trough, a major earthquake zone where the Philippine Sea Plate slides beneath the Eurasian Plate.
Hydrogeophysicist Josh Edgington compared the slow quake to “a ripple moving across the plate interface,” acting like a tectonic shock absorber that relieves pressure quietly and slowly. These findings confirm theories that such quakes influence the buildup or release of stress, which could eventually lead to a massive earthquake or tsunami.
This part of the Pacific Ring of Fire is known for violent geological activity, and the technology used here allows scientists to detect tiny shifts in the Earth’s crust sometimes just a few millimeters. This precision is crucial, especially for earthquake-prone regions like Cascadia (off the west coast of North America), which lacks the same “shock absorber” protection as Nankai and could potentially face a devastating magnitude 9 earthquake.
Geophysicist Demian Saffer emphasized that high-tech monitoring, like what was used in this study, is urgently needed in Cascadia. “Are there creaks and groans indicating strain release or is it deadly silent?” he asked, highlighting the importance of early detection.
The study also revealed that high underground fluid pressure may play a role in these slow quakes, and that different parts of the fault might behave independently a discovery that could change how scientists model earthquake risk.
While exact earthquake prediction remains a challenge, research like this is bringing us closer. Every new piece of data, especially from slow motion earthquakes, helps scientists improve forecasting models potentially saving thousands of lives in the future.
