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Post ShakeAlert Message Summaries


Post ShakeAlert Message Summaries provide information about earthquakes detected by the USGS component of ShakeAlert Earthquake Early Warning System (see graphic below). They summarize how accurately the ShakeAlert system estimated an earthquake’s location, magnitude, shaking intensities, how much warning time for selected nearby cities, and how many seismic stations contributed data to these estimates. Estimated warning times on the summaries does not include the additional time it takes for ShakeAlert Licensed Operators to deliver alerts to end-users (e.g. alert delivery to cell phones). Summaries are automatically generated for earthquakes with an estimated peak magnitude (M) of 3.5 or larger. For earthquakes estimated at M4.0 or larger, ShakeAlert Messages are human-reviewed and forwarded to the USGS Earthquake Hazards Program to be posted at www.earthquake.usgs.gov.  ShakeAlert produces summaries for earthquakes less than M4.0 to test software readiness, but the results are generally not reviewed for quality or accuracy. 

Roles of the USGS and Technical Partners in the ShakeAlert System. This graphic is available in the ShakeAlert Messaging Toolkit.

Please Note: USGS does not warrant that this information resource will be available without interruption, be error-free, or that any errors must be corrected. Post ShakeAlert Message Summaries are provided “AS IS” and without any warranty, express, implied, or otherwise, regarding its accuracy or performance. Any reliance upon this resource is at the express and sole risk of the user, including its employees, assigns, and insurers.

FileDate PostedSize
1138_2019-07-05_003206_19_miles_NE_of_Ridgecrest_3_89.pdf
July 05, 2019 269.90 KB
1137_2019-07-05_001748_12_miles_E_of_Ridgecrest_1_61.pdf
July 05, 2019 267.63 KB
1136_2019-07-04_234233_16_miles_NE_of_Ridgecrest_3_55.pdf
July 04, 2019 277.12 KB
1135_2019-07-04_233400_13_miles_E_of_Ridgecrest_3_91.pdf
July 04, 2019 274.71 KB
1134_2019-07-04_231240_18_miles_E_of_Ridgecrest_3_49.pdf
July 04, 2019 270.56 KB
1131_2019-07-04_214033_14_miles_E_of_Ridgecrest_3_42.pdf
July 04, 2019 273.70 KB
1130_2019-07-04_201450_16_miles_NE_of_Ridgecrest_3_98.pdf
July 04, 2019 273.49 KB
1115_2019-07-03_030405_17_miles_E_of_Cloverdale_3_4.pdf
July 03, 2019 306.69 KB
1096_2019-06-23_035302_29_miles_SW_of_Rio_Dell_5_53.pdf
June 23, 2019 205.16 KB
1090_2019-06-06_225246_2_miles_E_of_La_Habra_5_3839.pdf
June 18, 2019 289.88 KB
1091_2019-06-10_024111_16_miles_E_of_Bakersfield_3_53.pdf
June 18, 2019 318.66 KB
1092_2019-06-11_074625_16_miles_E_of_Cloverdale_3_72.pdf
June 18, 2019 304.41 KB
1093_2019-06-11_205838_15_miles_NW_of_Tracy_3_1.pdf
June 18, 2019 373.57 KB
1094_2019-06-13_000733_15_miles_S_of_Camarillo_3_63.pdf
June 18, 2019 284.60 KB