Overview

• MIT researchers quantified energy partitioning in laboratory earthquakes, finding roughly 80% converts to heat, about 10% produces shaking, and less than 1% creates new fractures.
• Sensors recorded microsecond temperature spikes up to about 1,200°C with brief melting near the fault, and one event implied roughly 10 meters per second slip over about 100 microns.
• The energy distribution depended on a sample’s deformation history, suggesting prior tectonic disturbance influences how future ruptures release energy.
• The team used powdered granite mixed with magnetic particles as internal thermometers, applied controlled loading with pistons and a gold jacket, and measured shaking with custom piezoelectric sensors.
• The peer-reviewed study, published Aug. 28 in AGU Advances with National Science Foundation support, offers mechanistic insights to improve earthquake models but does not directly translate to field-scale hazard forecasts.