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Beyond the teleseism: Introducing regional seismic and geodetic data into routine USGS finite‐fault modeling

Dara Elyse Goldberg·Pablo Koch·Diego Melgar·Sebastian Riquelme·William L. Yeck
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Abstract

The U.S. Geological Survey (USGS) National Earthquake Information Center (NEIC) routinely produces finite‐fault models following significant earthquakes. These models are spatiotemporal estimates of coseismic slip critical to constraining downstream response products such as ShakeMap ground motion estimates, Prompt Assessment of Global Earthquake for Response loss estimates, and ground failure assessments. Because large earthquakes can involve slip over tens to hundreds of kilometers, point‐source approximations are insufficient, and it is vital to rapidly assess the amount, timing, and location of slip along the fault. Initially, the USGS finite‐fault products were computed in the first several hours after a significant earthquake, using teleseismic body wave and surface wave observations. With only teleseismic waveforms, it is generally possible to obtain a reliable model for earthquakes of magnitude 7 and larger. Here, we detail newly implemented updates to NEIC’s modeling capabilities, specifically to allow joint modeling of local‐to‐regional strong‐motion accelerometer, Global Navigation Satellite System (GNSS), and Interferometric Synthetic Aperture Radar (InSAR) observations in addition to teleseismic waveforms. We present joint inversion results for the 2015 M w ">

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Dara Elyse Goldberg, Pablo Koch, Diego Melgar, Sebastian Riquelme, William L. Yeck. 2022-08-04. Beyond the teleseism: Introducing regional seismic and geodetic data into routine USGS finite‐fault modeling. https://doi.org/10.1785/0220220047

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