Detection of ground motions using high-rate GPS time-series

Psimoulis, Panos; Houlié, Nicolas; Habboub, Mohammed; Michel, Clotaire; Rothacher, Markus

Abstract

Monitoring surface deformation in real-time help at planning and protecting infrastructures and populations, manage sensitive production (i.e. SEVESO-type) and mitigate long-term consequences of modifications implemented. We present RT-SHAKE, an algorithm developed to detect ground motions associated with landslides, sub-surface collapses, subsidences, earthquakes or rock falls. RT-SHAKE detects first transient changes in individual GPS time series before investigating for spatial correlation(s) of observations made at neighbouring GPS sites and eventually issue a motion warning. In order to assess our algorithm on fast (seconds to minute), large (from 1cm to meters) and spatially consistent surface motions, we use the 1Hz GEONET GNSS network data of the Tohoku-Oki MW9.0 2011 as a test scenario. We show the delay of detection of seismic wave arrival by GPS records is of ~10 seconds with respect to an identical analysis based on strong-motion data and this time delay depends on the level of the time-variable noise. Nevertheless, based on the analysis of the GPS network noise level and ground motion stochastic model, we show that RT-SHAKE can narrow the range of earthquake magnitude, by setting a lower threshold of detected earthquakes to MW6.5-7, if associated with a real-time automatic earthquake location system.

Citation

Psimoulis, P., Houlié, N., Habboub, M., Michel, C., & Rothacher, M. (2018). Detection of ground motions using high-rate GPS time-series. Geophysical Journal International, 214(2), 1237–1251. https://doi.org/10.1093/gji/ggy198

• Journal Article Type: Article
• Acceptance Date: May 17, 2018
• Online Publication Date: May 18, 2018
• Publication Date: 2018-08
• Deposit Date: May 30, 2018
• Publicly Available Date: May 30, 2018
• Journal: Geophysical Journal International
• Print ISSN: 0956-540X
• Electronic ISSN: 1365-246X
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 214
• Issue: 2
• Pages: 1237–1251
• DOI: https://doi.org/10.1093/gji/ggy198
• Keywords: Earthquake Early Warning, GPS, detection, seismic signal, 2011 Tohoku-Oki, RT-SHAKE
• Public URL: https://nottingham-repository.worktribe.com/output/932953
• Publisher URL: https://academic.oup.com/gji/advance-article/doi/10.1093/gji/ggy198/4999902
• Additional Information: This article has been accepted for publication in Geophysical Journal International ©:2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
• Contract Date: May 30, 2018