The 1755 Lisbon earthquake

Abstract

Affecting an area of ca. 800 000 km2and killing up to 100 000 people, the Lisbon earthquake of 1755 is probably the greatest seismic disaster to have struck western Europe. The shock waves of the earthquake placed a temporary brake on the emerging rationalism of the European Enlightenment and attempts to explain the disaster in terms of human sinfulness coloured many contemporary accounts. Notwithstanding these difficulties, through careful archival research it has proved possible to obtain relatively value-free accounts of most aspects of the earthquake and to use these not only to model the physical characteristics of and damage caused by the earthquake, but also to consider the implications for present day hazard assessment and urban planning. This paper reviews the progress that has been made in: identifying source and faulting mechanisms; the processes involved in the generation and impact of tsunamis; damage caused to different types of building and the use being made of historical earthquakes of different sizes - of which the 1755 event is the largest - in defining future hazard scenarios for Lisbon and other areas of Iberia.