Abstract: At local time 3:36 on August 24, 2016, an M_s6.2 earthquake hit the town of Norcia in Lazio Rieti Province of central Italy. Despite that the earthquake magnitude was not big, some ancient towns were severely damaged. In this paper we revealed the causes of the abnormal damage by analyzing the architectural structure, geological structure, and topographic features in the study area according to monitoring achievements of seismic response of slopes in recent years in association with numerical simulation. Results uncover that terrain amplification effect could give rise to severe seismic disaster in spite of small magnitude and long distance to the epicenter. The poor seismic performance of aged buildings, the shallow seismic focus, the amplification effect of seismic wave induced by isolated topography are key factors resulting in the large number of casualties.

Key words: M_s6.2 earthquake in Norcia, Italy, abnormal damage, building structure, geological condition, terrain amplification