Seismic Hazard in Buenos Aires, Argentina, considering the influence of site effects and long-distance earthquakes

Buenos Aires, the capital and largest city of Argentina, is located on the southern shore of the Rio de la Plata, hundreds of kilometers away from the seismically active areas in the west of the country. For this reason, and despite evidence from both historical and recent events, earthquake hazards in this area have been traditionally neglected. Based on a series of unprecedented ground motions recorded in the city, this paper presents a review of the seismic hazard in the city of Buenos Aires. In order to do so, a site-specific probabilistic seismic hazard assessment is conducted considering (i) the higher rate of moderate local intraplate earthquakes observed in this area compared to the rest of Argentina's stable region, (ii) the significant site amplification produced by the soil deposit, and (iii) the influence of long-distance earthquakes. The results suggest that site-specific seismic design criteria are needed in Buenos Aires. A series of uniform hazard spectra are recommended for such purpose.