MIT triggers 'lab quakes' to decode earthquake energy distribution

Researchers at MIT have, for the first time, quantified the complete energy budget of an earthquake by creating controlled “lab quakes” that simulate seismic events on a miniature scale. Their experiments revealed that only about 10% of an earthquake’s total energy is responsible for the familiar ground shaking, while up to 80% is converted into heat, and less than 1% goes into fracturing rocks. Remarkably, this rapid heating can cause the rock near the fault to briefly reach temperatures as high as 1,200 degrees Celsius, effectively melting the surrounding rock before it quickly cools once the motion stops. To achieve these insights, the team used granite samples mixed with magnetic particles acting as thermometers, placed under pressure to mimic conditions deep in the Earth’s crust where earthquakes originate. They measured heat through changes in magnetic particle orientation, shaking via piezoelectric sensors and computer models, and fracturing by microscopic examination. The study also found that the energy distribution varies depending on the “deformation