CTBT: Science and Technology Conference 2025 - SnT2025

Data quality control of P- and S-wave picking of local earthquakes

P3.5-050

Not scheduled

20m

Zeremoniensaal

E-poster T3.5 Analysis of Seismic, Hydroacoustic and Infrasound Monitoring Data P3.5 Analysis of Seismic, Hydroacoustic and Infrasound Monitoring Data

Speaker

Moad Chikh (Centre National de Recherche Appliquee en Genie Parasismique (CGS))

Description

For the accurate determination of local earthquake hypocenters, it is necessary to have reliable and good quality P- and S-wave readings. Data quality control is an important step to correct or filter anomalies that can occur during phase picking. The Chatelain method (Chatelain, 1978) is first applied to facilitate VP/VS ratio calculation. This method is based on calculating the differences between P- and S-waves arrival times between all stations that record the same earthquake. The plot on the same graph of all S-phase differences vs P-phase differences between each pair of stations for all the studied earthquakes over a region in which the VP/VS ratio is supposed to be uniform is used to get the average VP/VS ratio. We then check the points that are outside the scheme, and evidence phase picking anomalies that need to be checked and provide corrections at the concerned station.