Shallow destructive earthquakes

Abstract

Depths of earthquake occurrence and large slip distribution are critical for seismic hazard assessment. Numerous examples show that earthquakes with similar magnitudes, however, can result in significantly different ground shaking and damage. One of the critical factors is that whether the large slip was generated near the ground surface. In this article, we reviewed two aspects that are important on this regard, shallow slip deficit and nucleation depth. Understanding how shallow future earthquakes may nucleate in particular regions, such as shale gas fields, is critical for hazard assessment. Whether or not a strong earthquake may slip significantly at shallow depths (less than 3 km) plays crucial rules in seismic hazard preparation and should be further investigated by integrating high-resolution fault zone observations, dynamic rupture simulation, and fault zone properties. Moreover, precisely resolving shallow depth and slip distribution of earthquakes demands InSAR and/or other image data that can better capture the near-fault deformation to constrain the source parameters of earthquakes.