Rapid magnitude estimation and coseismic deformation extraction from high-rate GNSS data: a case of the 2023 Turkey Mw7.8 and Mw7.7 earthquakes

Abstract Rapid magnitude estimation and precise coseismic deformation extraction are fundamental to effective earthquake emergency response and impact assessment. Here, we demonstrate the utility of high-rate Global Navigation Satellite System (GNSS) technology through a detailed analysis of the 2023 Turkey Mw7.8 and Mw7.7 earthquakes. By processing data from 20 stations using precise point positioning, we derived displacement waveforms and Peak Ground Displacement (PGD) values. While PGD generally decay with hypocentral distance, values are elevated along the bilateral rupture propagation path, reflecting directivity effects. Through accuracy assessment and sensitivity testing, we obtained robust magnitude estimates for Mw7.86 and Mw7.72 by applying the empirical PGD scaling law, which are consistent with the reported values. The coseismic deformation field extracted directly from the high-rate GNSS displacement waveforms aligns closely with the published results, all of which show obvious strike-slip characteristics. A key advantage is its ability to isolate pure coseismic static offset, avoiding the postseismic signal contamination that can complicate traditional geodetic analyses. Our findings firmly establish high-rate GNSS as a vital and reliable technology for earthquake early warning and rapid disaster assessment immediately following major seismic events.