The CESIS project: a new satellite seismic and CGPS network in Southern Italy to study plate boundary deformation in the Central Mediterranean

Abstract

The collision between Africa and Eurasia is associated with a complex pattern of deformation within the plate boundary zone, with subduction of oceanic fragments, crustal extension along formerly contracting orogenic belts and back-arc spreading in Tertiary basins. First-order scientific problems regarding the existence of rigid blocks within the plate boundary, the present-day activity of the Calabrian slab and the regional crust and upper mantle structures are still awaiting for a better understanding. Established in 2002 by the INGV (Istituto Nazionale di Geofisica e Vulcanologia) the CESIS project is deploying a permanent, integrated and real time monitoring system of 60 co-located permanent GPS and broad band seismometers in Southern Italy. The network is connected to the acquisition centre (located in Rome and duplicated in Grottaminarda) by a satellite system (VSAT). 50 seismic stations will be equipped with broad-band (0.033-40 Hz) seismometers and accelerometers, while 10 will be equipped with very broad-band seismometers. All the sites will be equipped with 1 Hz CGPS receivers. The research activity resulting from the data coming from the CESIS network will thus exploit the full range of temporal and spatial frequencies that characterize plate boundary deformation, allowing a large range of scientific problems, ranging from earthquake source studies to regional plate kinematics, to be tackled. Some of the most intriguing targets concern (a) the study of present activity of the Calabrian slab and its associated crustal deformation, (b) the southern boundary of the Adriatic block (a rigid microplate whose existence have been proposed on the basis of seismicity distribution, earthquake slip-vectors, and space geodesy), and (c) the monitoring of strain build-up along seismogenic faults. We present (a) the technical description of seismic and geodetic data acquisition, (b) the GPS and seismic stations monumentation, (c) the planned and existing site distribution, (d) the flow and archiving of seismic and geodetic data, and (e) first results of data analysis.