TSUNAMI INFORMATION STATEMENT NUMBER 1 NWS PACIFIC TSUNAMI WARNING CENTER EWA BEACH HI 0735 UTC WED JUN 14 2017 ...PTWC TSUNAMI INFORMATION STATEMENT... PRELIMINARY EARTHQUAKE PARAMETERS --------------------------------- * MAGNITUDE 7.0 * ORIGIN TIME 0729 UTC JUN 14 2017 * COORDINATES 14.9 NORTH 92.0 WEST * DEPTH 98 KM / 61 MILES * LOCATION NEAR THE COAST OF CHIAPAS MEXICO EVALUATION ---------- * AN EARTHQUAKE WITH A PRELIMINARY MAGNITUDE OF 7.0 OCCURRED NEAR THE COAST OF CHIAPAS, MEXICO AT 0729 UTC ON WEDNESDAY JUNE 14 2017. * BASED ON ALL AVAILABLE DATA... THERE IS NO TSUNAMI THREAT FROM THIS EARTHQUAKE. RECOMMENDED ACTIONS ------------------- * NO ACTION IS REQUIRED. NEXT UPDATE AND ADDITIONAL INFORMATION -------------------------------------- * THIS WILL BE THE ONLY STATEMENT ISSUED FOR THIS EVENT UNLESS ADDITIONAL DATA ARE RECEIVED OR THE SITUATION CHANGES.
USGS: How large does an earthquake have to be to cause a tsunami?
Magnitudes below 6.5
Earthquakes of this magnitude are very unlikely to trigger a tsunami.Magnitudes between 6.5 and 7.5
Earthquakes of this size do not usually produce destructive tsunamis. However, small sea level changes may be observed in the vicinity of the epicenter. Tsunamis capable of producing damage or casualties are rare in this magnitude range but have occurred due to secondary effects such as landslides or submarine slumps.Magnitudes between 7.6 and 7.8
Earthquakes of this size may produce destructive tsunamis especially near the epicenter; at greater distances small sea level changes may be observed. Tsunamis capable of producing damage at great distances are rare in the magnitude range.Magnitude 7.9 and greater
Destructive local tsunamis are possible near the epicenter, and significant sea level changes and damage may occur in a broader region.Note that with a magnitude 9.0 earthquake, the probability of an aftershock with a magnitude exceeding 7.5 is not negligible. To date, the largest aftershock recorded has been magnitude 7.1 that did not produce a damaging tsunami.
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