Reflection On Some 21st Century Earthquakes

December 10, 2020

This paper attempts to reflect on the question of how have we fared over the seismic events in the 21st century. By means of select events, some of the important recent lessons are highlighted, and areas for further improvement of our capacity in mitigating earthquake impacts are explored:
  • Increased Potential Earthquake Casualty with Rapid Densification of Population in Vulnerable Urban Centres – This trend is particularly acute in developing countries, where the seismo-tectonic setting of urban site and poor condition of built environment often constitute a physical death trap for its inhabitants;
  • Under-estimation of Seismic Hazard – Geological input in seismic hazard evaluation sometimes lags behind geoscience advancement. In other words, incorporation of appropriate seismic criteria for the design of building and infrastructure is often promulgated only after a devastating earthquake.
  • Severity of Traditional and Compounded Earthquake Secondary Impact – with increased population density and modern industrial development, the scope and severity of earthquake secondary impact are often underestimated and inadequately prepared for;
  • Advancement of Earthquake Monitoring and Understanding – the advancement continues, especially for a few major seismic events both before and after their occurrences, although many challenges remain; and
  • Evolution of Societal Response to Earthquake – with increasingly sophistication of modern society and ongoing improvement of earthquake knowledge, our societal response to a significant seismic event is also undergoing inevitable changes. Some observations of these changes are briefly discussed.
Earthquake is a natural hazard whose impact on our life is influenced to some degree by the development of our civilization. Although earthquake per se does not kill, failures of natural and/or built environment caused by it, do. Wittingly or not, the high population density in our cities, attainable because of our technological development, also exposes us all to increased vulnerability to earthquake destruction. Presented herein are some issues worthy of our collective reflection. Lo, R. 2017. “Reflection On Some 21st Century Earthquakes,” in 16th World Conference on Earthquake Engineering, January 9-13, 2017. Santiago, Chile.