Researchers: William D. Barnhart, University of Iowa, Gavin P. Hayes and David J. Wald, U.S. Geological Survey.
Written by Linda Rowan
18 September 2019
The National Earthquake Information Center (NEIC) of the U.S. Geological Survey is responsible for responding to earthquakes around the world and providing information to help with preparedness and response to these events. The expansion of Earth imaging satellites has expanded capabilities for geodetic observations and satellite imagery to describe earthquakes and their impacts on timescales helpful for earthquake response. This article describes several examples of integrating satellite imagery for earthquakes into event information products and a rapid workflow for incorporating geodetic data into earthquake information for public awareness.
The U.S. Geological Survey observes earthquakes around the world with a suite of seismometers. Increasingly, geodetic tools, such as GNSS sites and satellite imagery are being used to supplement seismic observations in operational earthquake monitoring and response. More open-source imaging satellites are available to observe earthquakes than just half a decade ago, especially Landsat-8, Sentinel 1 and 2, and commercial imagery available under the International Disaster Charter. This data allows the USGS and others to observe the deformation associated with many more events in a timely fashion over a dense spatial scale that supports earthquake response efforts following impactful events. Here the authors review the advantages and integration of satellite-derived earthquake information directly into operational earthquake response products at the NEIC.
The NEIC provides event response products such as ShakeMap (estimate or measurements of ground shaking induced by the earthquake), Prompt Assessment of Global Earthquakes for Response (PAGER, estimate of expected fatalities and economic losses from exposure to shaking), a fault model for events larger than a magnitude 7, estimates of the likely ground failure due to landslides or liquefaction and for historical/probabilistic efforts an earthquake catalog. Analysis shows that satellite imagery can help to locate the event, determine the amount and direction of motion along the fault, enhance the fault model with spatial details about the slip, and provide further calibration of ShakeMap shaking estimates Most importantly, rapid access to frequently acquired radar and optical imagery occurs on timescales, less than 2.5 days after the earthquake on average, when they can provide impactful response information. Ongoing and future efforts seek to systematically include geodetic-based earthquake information into rapid response workflows so as to provide the most complete description about an earthquake for effective operational disaster response.
W.D. Barnhart, G.P. Hayes and D. J. Wald, Global Earthquake Response with Imaging Geodesy: Recent Examples from the USGS NEIC, Remote Sens. 2019, 11, 1357; doi: 10.3390/rs11111357.
satellite imagery, earthquake, fault model, slip
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Last modified: 2020-01-28 22:16:20 America/Denver