Update on monitoring of magnetic and electromagnetic tectonic signals in Central Italy

Abstract

A network of three absolute magnetometer stations and the geomagnetic observatory of L’Aquila (42°23N, 13°19E) monitors possible seismo- or tectonomagnetic effects in Central Italy, using L’Aquila Observatory as a reference for differentiation. A system of two VLF search coil wide-band antennas, working in two different frequency bands, at the L’Aquila Observatory, monitors possible electromagnetic effects related to seismic events occurring in Central Italy. Absolute magnetic field observations and VLF signals have been collected for several years. In particular the tectono-magnetic network started its operations in 1989. In this paper we report on the time variation of above mentioned data for the most recent years 2002 and 2003, also in connection with older measurements time series; we also report on seismic activity recorded in this area by the national seismic network. In the above mentioned time interval, no strong earthquake activity was recorded, and at the same time no clear evidence for magnetic or electromagnetic signals related to seismic events was found.