Author(s)

Abdelouaheb Agrebi^1*, Andry Harifidy Ramanantsoa², Gerard Rambolamanana³, Eddy Harilala Rasolomanana⁴

¹On-Site Inspection Division, CTBTO, Vienna, Austria.
²Laboratoire de Séismologie et d’Infrason, Institut et Observatoire de Géophysique, Université Antananarivo, Antananarivo, Madagascar.
³International Data Centre, CTBTO, Vienna, Austria.
⁴Ecole doctorale ingénierie et géosciences, Université d’Antananarivo, Ecole Polytechnique, Antananarivo, Madagascar.

The I48TN is one of the 60 International Monitoring System (IMS) stations of the Comprehensive nuclear Test Ban Treaty Organization (CTBTO), characterized by its location in the heart of the IMS Infrasound network. The ability of the International Monitoring System (IMS) infrasound network to detect atmospheric nuclear explosions and other signals of interest is strongly dependent on station-specific ambient noise. This ambient noise, includes both incoherent wind noise and real coherent infrasonic waves. Infrasound analysis software detects tens to hundreds of events per day which consume a lot of time for the Infrasound analysts, to define and categorize events where around 90% of the detections are coherent noise. This study analyzed the importance of the synergy between infrasound and seismic data, and provided the infrasound data analyst with the most important local coherent infrasound sources in the region as recorded by the IMS station I48TN, in order to reduce the workload of the analysts and give them a clear view on the coherent noise affecting this station for better discrimination between events of interest like nuclear explosions and coherent sources. DTK_GPMCC and DIVA software were used to perform this study. Geotool software from the International Data Centre (IDC) was used in analysing seismic data from the Tunisian IMS station KEST. The result of this study allowed the characterization of the most important coherent local infrasound sources (Mines and Quarries) which are considered as coherent noise to I48TN station and correct parameters in some reference events in the Reference Event Database source of the International Data Centre.

Mines and Quarries, Infrasound Stations, Infrasound Local Sources, Acoustic Energy

Agrebi, A. , Ramanantsoa, A. , Rambolamanana, G. and Rasolomanana, E. (2021) Characterisation of the Coherent Infrasound Sources Recorded by the Infrasound International Monitoring System Station I48TN in Tunisia (Mines & Quarries). Atmospheric and Climate Sciences, 11, 214-243. doi: 10.4236/acs.2021.111014.