Deformation rates and localization of an active fault system

The Corinth Rift in Greece is one of the most active extensional regions in the Mediterranean area (Fig. 1). The Corinth Rift Laboratory project (CRL, http://crlab.eu) is based on the cooperation of various european institutions that merge their efforts to study fault mechanics and related hazards in this natural laboratory where numerous continuous observations are made. The present rift is asymmetric and deformation is very localized. Numerous GPS campaigns since 1991 indicate a stable opening rate of about 1.5 cm/yr over a width of 10- 12 km in the western part of the rift (Fig. 2). Continuous GPS stations installed 10 years ago start to reveal reliable vertical displacement (Fig.3). The seismic activity is localized in the upper 12 Km of the crust. Although the 3D geometry of active faults might be quite complex (Fig. 4), we present here a simple 2D mechanical model including one normal fault embedded in an elasto-visco-plastic medium, aimed at exploring crustal rheology and fault parameters able to explain both horizontal extension rates and vertical deformation.