The Agadir seismic database is fed by a local seismic network of five stations. The latter belongs to the national seismic network of Morocco. Three types of seismic events are recorded on daily basis: earthquakes, quarry blasts, and other undesired seismic events which are considered as noise. A quantity of data is currently available. The aim of this study is to highlight the degree of similarity that may exist between these different seismic events. This similarity could help in many studies including classification of these seismic events. The cross-correlation function, commonly used in signal theory, is used to quantify this similarity and compare the obtained results. The cross-correlation function is firstly applied to synthetic signals to clearly demonstrate its behavior versus signal parameter variation, and then to real seismic signals. The obtained results show that quarry blast signals are more correlated than those of earthquakes. This is explained by different factors. This relative correlation that exists between quarry blast signals may be exploited to develop an identification task.

Cross-correlation, Seismic signal, Similarity, Classification

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