Identifying the activation of an inland fault for the first time in Malta

Abstract

A key prerequisite to efficiently monitor seismic activity is the appropriate planning and deployment of seismic stations of a local network. The effectiveness of a recently extended local network in the Maltese Islands and applications of various methodologies on its data, are presented and further discussed. Using the data of the enhanced network, it was possible for the first time to identify the activation of an inland fault. Such accomplishment is important not only because it sheds light to the local tectonics but also contributes to an accurate seismic hazard assessment of the Maltese islands. Since 1995 and until 2014 only one broadband station was installed on the island. The detection of several local events, using a single station location algorithm, indicated the need to improve earthquake locations and detectability. The Malta Seismic Network (ML) in the recent years was extended and currently comprises six broadband stations. Between June 2017 and September 2018, and in collaboration with Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS) in the frame of the project FASTMIT, 6 short period new stations were installed in key positions across the islands. This temporary network improved the overall network capability and served also to test new sites for permanent station locations. [excerpt]