Application of 1-second Precise Point Positioning (PPP) results to detecting the time of earthquake impact on GNSS permanent station

Abstract

Determining the exact time when seismic waves impact different locations in an earthquake area will help us better understand the earthquake mechanism and the structure of the earth's crust. If permanent GNSS stations are installed in the earthquake area, in principle, based on their coordinate series, we can determine the time of impact. We consider the processing of precise point positioning for data of GNSS stations with an interval of 1-second and test the processing for 4 stations at the Noto earthquake (Japan) on January 1, 2024. The coordinate series resulting from our PPPC software and from the online processing service CSRS-PPP of the Ministry of Natural Resources of Canada are completely similar to each other. Based on these series, we can accurately determine the time when the station was affected by the earthquake. Moreover, they also ensure the accuracy of determining the instantaneous displacement of the station immediately after the earthquake.