Les enseignements du petit séisme de Peille (Alpes-Maritimes, France)

Abstract

The Peille earthquake (M_w=3.4) occurred on 1st November 1999, 15 km to the north of the cities of Nice, Monaco and Menton. This event was very well recorded by 20 seismological stations located between 6 and 50 km from the epicenter. We used a non-linear location method and showed that the earthquake occurred at shallow depth (3±1.5 km) close to the Peille–Laghet fault trace. Moreover the computed focal mechanism is consistent with the left lateral strike slip movement of this fault. An empirical Green's function deconvolution showed that the rupture occurred on a fault portion smaller than 600 m long. This earthquake was also the occasion to point out remarkable site effect amplifications in some areas of the city of Nice.