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High-rate GPS positioning has been recognized as a powerful tool in estimating epoch-wise station displacement which is particularly useful for seismology. In this study, station displacements during the 12 May 2008 M w 8.0 Wenchuan earthquake are derived from the 1-Hz GPS data collected at a set of stations in China. The impacts of integer ambiguity resolution and station environmentdependent effects are investigated in order to yield more accurate results. The position accuracy of horizontal components of better than 1 cm suggests that GPS can sense the rapid position oscillation of about 2 cm in amplitude. Temporal and spatial analysis is applied to the surface displacement at station XANY and the characteristics of the movements due to Rayleigh and Love waves are detected and discussed. The comparison of GPS derived displacement with relevant synthetic data computed based on a recently published rapture model shows a reasonable agreement in waveform. The various differences in amplitude need further investigation and also imply that rapture inversion might be

The variometric approach is investigated to measure real‐time seismic waves induced by the 2015 Mw 7.8 Nepal earthquake with high‐rate multi‐GNSS observations, especially with the contribution of newly available BDS. The velocity estimation using GPS + BDS shows an additional improvement of around 20% with respect to GPS‐only solutions. We also reconstruct displacements by integrating GNSS‐derived velocities after a linear trend removal (IGV). The displacement waveforms with accuracy of better than 5 cm are derived when postprocessed GPS precise point positioning results are used as ground truth, even if those stations have strong ground motions and static offsets of up to 1–2 m. GNSS‐derived velocity and displacement waveforms with the variometric approach are in good agreement with results from strong motion data. We therefore conclude that it is feasible to capture real‐time seismic waves with multi‐GNSS observations using the IGV‐enhanced variometric approach, which has critical implications for earthquake early warning, tsunami forecasting, and rapid hazard assessment.

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