Using 1-Hz GPS data to measure deformations caused by the denali fault earthquake

K.M. Larson; P. Bodin; J. Gomberg

doi:10.1126/science.1084531

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Using 1-Hz GPS data to measure deformations caused by the denali fault earthquake

K.M. Larson·P. Bodin·J. Gomberg

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Abstract

The 3 November 2002 moment magnitude 7.9 Denali fault earthquake generated large, permanent surface displacements in Alaska and large-amplitude surface waves throughout western North America. We find good agreement between strong ground-motion records integrated to displacement and 1-hertz Global Positioning System (GPS) position estimates collected ??? 140 kilometers from the earthquake epicenter. One-hertz GPS receivers also detected seismic surface waves 750 to 3800 kilometers from the epicenter, whereas these waves saturated many of the seismic instruments in the same region. High-frequency GPS increases the dynamic range and frequency bandwidth of ground-motion observations, providing another tool for studying earthquake processes.

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K.M. Larson, P. Bodin, J. Gomberg. 2003. Using 1-Hz GPS data to measure deformations caused by the denali fault earthquake. https://doi.org/10.1126/science.1084531

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