Portugal

	Earthquake

Portugal Earthquake

Portugal lies on the western portion of the Iberian Peninsula. In this region, a complicated pattern of micro-plates, in relative motion with each other and with the other major tectonic plates, causes most of the seismic activity. Seismic hazard in Portugal results from inter- and intra-plate earthquakes, as well as onshore and offshore faults. Almost all of Portugal is susceptible to earthquakes, however they dominate the southern part of the country.

The most disastrous earthquake in Portugal’s history was the 1755 Lisbon Earthquake. It is the only historical earthquake in or near Portugal known to have a magnitude in excess of 8.0. The exact location and mechanics of this event are not exactly known, but the epicenter is believed to have been located in the Atlantic Ocean some 300 km southwest of Lisbon.

The earthquake was felt across most of North Africa and all of Europe. Lisbon was almost completely destroyed, with approximately 85% of the original houses left in ruin. This was one of the most devastating events in Europe’s history, illustrating the potential for low frequency, high magnitude events in Portugal. Since 1997, the RMS® Portugal Earthquake Model has been used by insurance and reinsurance companies to understand the implications of both the historical record and modern-day science on their current exposure to earthquake risk in Portugal.

Model Highlights

	Model developed with RMS research, and the cooperation of local experts
	Attenuation function adopted from those accepted by the Portuguese engineering seismology community
	11 earthquake source regions
	Single line source that accounts for the 1755 Libson Earthquake
	Return periods derived from historical data dating back to 1531 AD
	Building vulnerability curves developed from work of local experts and RMS research
	Landslide and liquefaction database
	Building code benchmark years of 1960 and 1986

Geographic Scope

All of continental Portugal

Exposure Data Resolution

Data input supported at the following levels of resolution: latitude-longitude, postal code, city, conselhos (county equivalent), and CRESTA zone