Abstract

In summary (Fig. 10.31), the potential areas most subject to large-magnitude earthquakes lie above the coupling region between the Nazca and South American plates, which corresponds to the contact region between the trench and approximately 45-53 km depth along the Wadati-Benioff region. Earthquakes in intraplate regions within the subducting Nazca Plate, which can reach magnitudes of the order of 8, are characterized by higher stress drops than events that take place in the contact between these two plates, thus producing higher accelerations at the surface. Large magnitude earthquakes are also generated at the transcurrent system between the South America and the Scotia plates. We have come a long way from the early reports of Maria Graham and Charles Darwin, and the overall controls on Chilean seismicity are clearly much better understood. Whilst future studies will continue to improve our knowledge of the seismic pattern, much work also needs to be done on prediction and damage limitation in this spectacularly earthquake-prone country.