Por João C. Duarte (Departamento de Ciências da Terra e Energia e Instituto Dom Luiz, FCUL).

Abstract: On the 1st of November 1755, a major earthquake struck the coast of Portugal. With a magnitude of ~8.7, this was the biggest earthquake ever to hit the Atlantic and Europe, causing widespread destruction and producing a tsunami that affected four different continents. On the 2nd of February 1969, another major 7.9 earthquake hit the Iberian Peninsula. In the last few decades, offshore marine geology and geophysics studies have allowed for mapping some of the main tectonic faults that may be responsible for the high-magnitude seismicity. However, none of these faults were able to explain the earthquakes of 1755 and 1969. Recent geophysical studies, accompanied by geodynamic numerical models, have provided new light on this long-lasting unsolved problem. In this presentation, I will provide a brief historical context, show some of the geophysical data and present some of the most recent numerical models that suggest an alternative explanation for the source of high-magnitude seismicity offshore Iberia. I will also briefly introduce the methods used in the study of plate tectonics and geodynamic modelling.