Monitoring Earthquake Mechanics under Evolving Natural TectOnic stress

Earthquakes pose a major threat to society, yet short-term forecasting remains elusive due to our limited understanding of how they initiate. Recent advances in seismology and geodesy have significantly enhanced the resolution of observations, revealing the stressed and fractured nature of the earthquake-hosting crust at plate boundaries. However, laboratory rock deformation studies still fall short—focusing on far-from-reality optimal fault orientations in intact elastic crust. MEMENTO—Monitoring Earthquake Mechanics under Evolving Natural TectOnic stress—will bridge this gap by replicating, for the first time, a critically stressed and highly fractured crust during the earthquake preparatory and nucleation phases, under diverse stress regimes, including pioneering experiments on extensional earthquakes.MEMENTO is structured around three main objectives: (1) decoding the role of a critically stressed crust in earthquake mechanics, (2) advancing experimental capabilities for simulating diverse tectonic stress conditions, and (3) integrating laboratory findings with natural seismic sequences using numerical and seismological tools.The project will employ a novel rock deformation prototype, DANTE—Deformation Apparatus simulating Natural Tectonic stress Evolution—to capture the interplay between stress, damage, and slip across the entire earthquake cycle and the full spectrum of tectonic stress regimes. MEMENTO will provide an unprecedented perspective on how diverse stress regimes govern earthquake precursors and nucleation.To ensure the relevance of laboratory findings to natural seismic sequences, MEMENTO will integrate experimental results with state-of-the-art quasi-dynamic simulations and high-resolution seismic observations. This upscaling effort bridges the gap between controlled experiments and real-world seismicity, establishing a new benchmark for understanding earthquake mechanics and informing the development of more reliable forecasting tools.