Possible source effects observed in a Magnetotelluric Monitoring site in Southern Italy

Since 2003 continuously operating magnetotelluric (MT) systems have been installed in Agri Valley (Southern Italy) by the Institute of Methodologies for the Environmental Analysis (IMAA). The valley is a NW-SE intermontane basin filled by middle Pleistocene alluvial deposits. The pre-quaternary bedrock is composed by Mesozoic-Cenozoic carbonates, mainly outcropping along the west site of the basin, while toward east and south-east, the bedrock is formed by Tertiary siliciclastic sediments. The valley of the Agri River is affected by a coherent fault system N120 trending left-lateral strike-slip fault. In recent years the Agri Valley has been interested by intensive oil extraction. In the present study the stability of the apparent resistivity values in several sites of Agri Valley is performed in order to find a site sufficiently "quiet" to be used as remote reference in a MT network.