Continental mantle earthquakes (CMEs) and their implications for the rheological structure of continents have fascinated geophysicists for more than half a century. Existence of these earthquakes is no longer debated, but their identification remains sparse across the globe. Comparing the Sn and Lg seismic wave amplitude ratio ( Sn/Lg ) of an earthquake with that of nearby earthquakes distinguishes CMEs and, unlike previous methods, can be applied globally. We present a global distribution of CMEs that extends well beyond previous individual detections and areas of speculation. CME occurrence is widespread globally yet patterned regionally, reflecting local lithospheric structure and tectonic history. Our results highlight the value of CMEs for understanding continents and global tectonics.
Wang et al. (Thu,) studied this question.