Evaluation of the Matched-Filter Approach for Detecting Seismic Phases, Case Study on a Local Network

Document Type : Research Article

Authors

1 Seismology, International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, Iran

2 Assistant Professor, Seismological Research Center, Department of Geology, International Institute of Seismology and Earthquake Engineering (IIEES), Tehran, Iran

Abstract

The first step in many seismological studies is identifying and locating the seismic events. The small magnitude earthquakes, due to their rate of occurrence and abundance, are of great importance to seismologists, contrary to the engineers and city residents. However, due to the attenuation of seismic waves and the unavoidable noise in the seismic stations, very dense seismographic networks are required for detecting small events. The Matched-Filter technique is an approach based on signal processing, which makes it possible for seismologists to identify the seismic phases with very low signal-to-noise ratios by improving the detection capability of the seismic networks in case of repeating events. The goal of this study is to depict the points that must be considered when employing the Matched-Filter approach. As a result, sensitivity tests were performed on each parameter to demonstrate their importance and effectiveness in influencing the outcomes of utilizing this technique on a local seismic network. The statistical studies revealed that selecting incorrect values reduces the quality of the identifications and may potentially result in mistakes. Finally, depending on the assessments and settings chosen, this method utilized to process 95 days of continuous data from a local temporary seismographic network demonstrates the technique's capability.

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