Mercantour: the biggest Alpine (paleo)earthquake? (2024)

Project description

The Bersezio-Serenne fault system is one of the most seismic in the western Alps. However, it has never experienced any devastating earthquakes in recent centuries. Is this seismic activity representative in the longer term? In the context of low deformation rates, can geological analyses provide complementary information to instrumental data? In recent years, morphological and paleoseismological studies of this fault system have revealed the occurrence of an Mw ≥ 6-6.5 earthquake over the last few millennia. We propose an approach combining high-resolution analysis of micro-topography and sub-surface imaging across the tectonic escarpment highlighted at Col de la Lombarde (Mercantour massif, near Isola 2000). Analysis and dating of the geometries of paleochannels offset by slip along this fault will enable us to reconstruct the amplitudes and chronology of major seismic events since the last ice age. Our aim is to improve our knowledge of the current tectonic regime in the Alps, and to answer key questions about regional seismic hazard.