Multi-sensor network for monitoring subsidence and seismic motion in Kalochori urban site, N. Greece

Abstract

An urban-scale approach for monitoring seismic motion and ground subsidence has been implemented in the broader area of Kalochori, western of Thessaloniki in Northern Greece, by means of a multi-sensor network within the ongoing INDES-MUSA project (www.indes-musa.gr); funded by the Greek General Secretariat of Research and Technology. The integrated network combines land-based and airborne monitoring techniques covering a wide area of different urban sites such as residential structures, critical facilities and civil infrastructures like industries and oil tanks. The permanent monitoring scheme includes accelerometric stations collocated with reference GNSS stations, water level stations, a tide gauge mounted on a jetty of the Thessaloniki port and LiDAR missions of 25km2 flight plan covering the whole area under investigation. Field campaigns with mobile GPS sensors and water level measurements are also deployed periodically, in the framework of ground subsidence monitoring, whereas focused geophysical arrays were performed at the locations of the accelerometric stations to obtain knowledge on the subsoil conditions. Following a brief description of the area under study, salient features of the monitoring network components are described and some original data is presented with emphasis on shear waves propagation velocity models obtained from geophysical arrays, representative acceleration recordings from recent earthquakes in Greece and a Digital Surface Model of the area obtained from the first LiDAR mission.