TSUNAMI INFORMATION STATEMENT NUMBER 1 NWS PACIFIC TSUNAMI WARNING CENTER EWA BEACH HI 0706 UTC TUE JUL 11 2017 ...PTWC TSUNAMI INFORMATION STATEMENT... EARTHQUAKE PARAMETERS (UPDATED WITH USGS INFO) --------------------------------- Region: Auckland Islands, New Zealand region Geographic coordinates: 49.546S, 164.031E Magnitude: 6.6 Depth: 10 km Universal Time (UTC): 11 Jul 2017 07:00:01 Time near the Epicenter: 11 Jul 2017 07:00:01 Local standard time in your area: 10 Jul 2017 21:00:01 Location with respect to nearby cities: 458.2 km (284.1 mi) SW of Bluff, New Zealand 475.6 km (294.9 mi) SW of Invercargill, New Zealand 530.7 km (329.0 mi) SW of Gore, New Zealand 611.9 km (379.4 mi) SW of Queenstown, New Zealand 634.1 km (393.1 mi) SW of Dunedin, New Zealand EVALUATION ---------- * AN EARTHQUAKE WITH A MAGNITUDE OF 6.6 OCCURRED IN THE AUCKLAND ISLANDS REGION OF NEW ZEALAND AT 0700 UTC ON TUESDAY JULY 11 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. * AUTHORITATIVE INFORMATION ABOUT THE EARTHQUAKE FROM THE U.S. GEOLOGICAL SURVEY CAN BE FOUND ON THE INTERNET AT EARTHQUAKE.USGS.GOV/EARTHQUAKES -ALL LOWER CASE-. * FURTHER INFORMATION ABOUT THIS EVENT MAY BE FOUND AT PTWC.WEATHER.GOV AND AT WWW.TSUNAMI.GOV. * COASTAL REGIONS OF HAWAII... AMERICAN SAMOA... GUAM... AND CNMI SHOULD REFER TO PACIFIC TSUNAMI WARNING CENTER MESSAGES SPECIFICALLY FOR THOSE PLACES THAT CAN BE FOUND AT PTWC.WEATHER.GOV. * COASTAL REGIONS OF CALIFORNIA... OREGON... WASHINGTON... BRITISH COLUMBIA AND ALASKA SHOULD ONLY REFER TO U.S. NATIONAL TSUNAMI WARNING CENTER MESSAGES THAT CAN BE FOUND AT NTWC.ARH.NOAA.GOV.
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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