In
addition to displaying earthquakes by magnitude, this service also
provide earthquake impact details. Impact is measured by population as
well as models for economic and fatality loss. For more details, see: PAGER Alerts.
Events are updated as
frequently as every 5 minutes and are available up to 30 days with the
following exceptions:
Events with a Magnitude LESS than 3.0 are retained for 3 daysEvents with a Magnitude LESS than 4.5 are retained for 7 days
In addition to event points, ShakeMaps are also provided. These
have been dissolved by Shake Intensity to reduce the Layer Complexity.The specific layers provided in this service have been Time Enabled and include:
Events by Magnitude: The event’s seismic magnitude value.Contains PAGER Alert Level: USGS PAGER (Prompt
Assessment of Global Earthquakes for Response) system provides an
automated impact level assignment that estimates fatality and economic
loss.Contains Significance Level: An event’s significance is determined by factors like magnitude, max MMI, ‘felt’ reports, and estimated impact.Shake Intensity: The Instrumental Intensity or Modified Mercalli Intensity (MMI) for available events.For field terms and technical details, see: ComCat DocumentationThis map is provided for informational purposes and is not monitored 24/7 for accuracy and currency. Always refer to USGS source for official guidance.
