Mechanics and statistics of postseismic shaking

Timothy Hugh Clements; Elizabeth S. Cochran; Sarah E. Minson; Nicholas van der Elst; Clara Yoon; Annemarie S. Baltay; Morgan T. Page

doi:10.1029/2025gl116673

USGS · 70271954

Mechanics and statistics of postseismic shaking

Timothy Hugh Clements·Elizabeth S. Cochran·Sarah E. Minson·Nicholas van der Elst·Clara Yoon·Annemarie S. Baltay·Morgan T. Page

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Abstract

Analysis of two weeks of continuous post-seismic shaking after the 2019 M7.1 Ridgecrest, CA earthquake sequence using 4 nearby borehole seismometers reveals that continuous ground motions decay as Omori’s law in time and follow the Gutenberg-Richter distribution in logarithmic amplitude. The measured temporal decay in amplitudes agrees with predictions of the rate-and-state framework and indicates shaking amplitudes are proportional to the velocity of afterslip. Our ground motion-based statistical framework provides a basis to forecast shaking intensity in the minutes to hours after a large earthquake.

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Geophysical Research Letters Article

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Timothy Hugh Clements, Elizabeth S. Cochran, Sarah E. Minson, Nicholas van der Elst, Clara Yoon, Annemarie S. Baltay, Morgan T. Page. 2025-09-12. Mechanics and statistics of postseismic shaking. https://doi.org/10.1029/2025gl116673

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