Input for assessing the impact of noisy data on earthquake magnitude estimates derived from peak ground displacement measured with real-time Global Navigation Satellite System data

This data release complements Murray et al. (2023) which presents a framework for incorporating earthquake magnitude estimates based on real-time Global Navigation Satellite System (GNSS) data into the ShakeAlert® earthquake early warning system for the west coast of the United States. Murray et al. (2023) assess the impact of time-dependent noise in GNSS real-time position estimates on the reliability of earthquake magnitudes estimated using such data. To do so they derived peak ground displacement (PGD) estimates from time series of background noise in GNSS real-time positions. These noise-only PGD measurements were used as input to a published empirical relationship to compute magnitude for hypothetical earthquakes that are each defined by an epicentral location and origin time. The data files provided here give the locations of GNSS stations used in the study, the hypothetical epicenters and origin times, and the PGD for each GNSS station for four time windows following each hypothetical origin time. We also provide the epicenters and origin times used to simulate the impact of noisy PGD data in terms of the annual number of spuriously large magnitude estimates that would be generated in the geographic region spanned by California, Oregon, and Washington, United States, due to noise alone. Finally, we include the estimated magnitudes for the annual simulations along with the number of GNSS stations for which the measured PGD exceeding a threshold value that was defined empirically to eliminate unreliable magnitude estimates.