Dynamic Full‐Field Imaging of Rupture Radiation: Material Contrast Governs Source Mechanism

Abstract In seismology, the rupture mechanisms of an earthquake, a glacier stick‐slip and landslide are not directly observed, but inferred from surface measurements. contrast, laboratory experiments can illuminate near field effects. The reflects mechanism is highly attenuated in case real‐world data. We image elastic wave‐field nucleating non‐invasively its near‐field with ultrasound speckle correlation. Our imaging yields particle velocity full shear wave at source location inside 3D frictional body. experimentally show that strong bimaterial as encountered environmental unidirectional or linear force for pre‐rupture microslips decelerating supershear ruptures. A weak characteristic earthquakes, generates double‐couple sub‐Rayleigh ruptures, sometimes preceded by slow deformation interface. This reproduced NF force.