Compiling a comprehensive seismic catalogue for tunisia using a new regional magnitude homogenisation equation
摘要
Earthquake catalogue is crucial for seismicity modeling and seismic hazard assessment. That’s why it should be updated, homogeneous and complete. This study presents a comprehensive compilation of the Tunisian seismicity catalogue. Our approach involved integrating instrumental and historical data, ensuring comprehensive coverage. Seismological data, including epicenters, origin times, location (longitude & latitude), and amplitudes, were collected from the Tunisian Seismic Network database which is installed by the National Institute of Meteorology for accurate earthquakes. Additionally, data from three other earthquake catalogues were incorporated which are data from the International Seismological Centre, the Euro-Mediterranean Seismological Centre, and the Algerian Centre for Research in Astronomy, Astrophysics and Geophysics. The updated earthquake catalogue spans from 412 to 2022, encompassing 5,932 events, with the moment magnitude scale established through a new magnitude homogenization equation specifically developed for the Tunisian region. This catalogue is the most updated one for Tunisian seismicity due to the exploitation of recent data detected by modern installed stations by the INM. In fact, it is identified by a notable increase in the total number of events nearly doubled compared to the previous elaborated catalogues. The generated b-value attends 0.83 which is a suitable one for a region with low to moderate seismicity such as Tunisia. Through a parametric study, we compared the computed b-value with those calculated previously and identified the factors and parameters that have the greatest influence on it which are the magnitude conversion and the amount of data treated.