The IberArray network: a tool to investigate the lithospheric structure of the Iberian plate

Abstract

IberArray is the observational platformofthe TOPO-IBERIA project (a five-year initiative funded by the Spanish Ministry of Education and Science that gathers approximately 125 researchers from 10 different Spanish research centers). IberArray network consists of 3 types of instruments: seismic (broad-band seismometers), geodetic (GPS), and magnetotelluric. The seismic network is composed of40 new portable broad-band stations that operate together with other existing permanent and portable broad-band stations in the region, forming an approximately regular network on a 60 km x 60 km grid that will cover the entire Iberian Peninsula and northern Morocco in three successive deployments, from south to north. In mid-2009, the first (southern) deployment in Spain was completed and instruments were moved to the second deployment in central Spain. We will present the current status and future deployment of the network, its relationship with similar deployments in Morocco, Portugal and France, and the principal results obtained so far. The first study conducted using data from the IberArray seismic network, consisted in analyzing the noise characteristics ofthe stations. We analyzed the major sources ofnoise at different frequency bands and their variations related to time of day, season, weather, location and type of installation, using power spectral density (PSD) estimates and their corresponding probability density functions (PDFs). In addition we will present results of the different studies currently underway to investigate the lithospheric structure of the Betics-Rif orogenic system. These include crustal imaging from ambient noise and travel-time tomography, variations in crustal thickness from receiver functions, and mantle anisotropy from SKS splitting analyses.