A new study has revealed the hidden mechanisms behind the formation of earthquakes, shedding light on the transition from slow, creeping motion to violent ruptures that shake the Earth.

This research, conducted by researchers at the Racah Institute of Physics at the Hebrew University of Jerusalem, challenges long-held assumptions about how earthquakes occur and offers new insights into seismic activity.

Led by Professor Jay Fineberg and doctoral student Shahar Gvirtzman, the team worked with experts from ETH Zurich and the Ecole Normale Superieure de Lyon.

Their results show that the slow, silent release of stress is not only a precursor but also a necessary trigger for seismic events.

By using advanced experiments and innovative theoretical models, the researchers showed how steady creep at critical stress thresholds can transition into dynamic ruptures associated with earthquakes.

The study highlights the often overlooked role of fault geometry in this process.

By incorporating the finite width of fault interfaces into their models, the researchers refined existing theories of earthquake triggering.

“Our results challenge and refine conventional models of fracture dynamics,” explained Prof. Fineberg. “We show that slow, aseismic processes are a prerequisite for seismic rupture caused by local stresses and geometric constraints.”

Key highlights include experimental validation using high-speed imaging techniques that captured how fracture nucleation begins as small, slow-moving patches of frictional motion.

These patches gradually expand until they develop into rapid dynamics typically described by classical fracture mechanics.

The implications of this research extend beyond earthquake science; They provide insights into material strength and fracture dynamics.

The study shows the importance of detecting slow, aseismic processes that often precede earthquakes. Seemingly quiet seismic precursors could contain important information about upcoming seismic events, potentially improving prediction models for future earthquakes.

This research not only deepens our understanding of one of nature’s most powerful forces, but also paves the way for improved methods to predict and mitigate earthquake risks worldwide.