Damage Assessment and Seismic Intensity Analysis of the 2010 (M w 8.8) Maule Earthquake

The MSK-64 seismic intensities inside the damage area of the 2010 Maule earthquake are estimated. With this purpose, field surveys of damage to typical single-family buildings located in 111 cities of the affected area were used. Cities located close to the north part of the earthquake rupture suffered higher damage, but most of this damage concerned adobe and unreinforced masonry houses. Minor and moderate damage was noted in modern low-rise engineered and nonengineered constructions, especially in confined masonry buildings. Despite the large length of the rupture, which reached more than 450 km, only one intensity value equal to IX was determined, and 21% of the values were greater than VII. The attenuation of seismic intensity was controlled by the distance to the main asperity more than to the hypocenter, which would be an important characteristic of the megathrust earthquakes, and it should therefore be considered in the seismic risk of large subduction environments.