VII
- M7.6 - Séisme de magnitude 7,6 à Hokkaido, au Japon. Alerte au tsunami émise.
Un séisme de magnitude 7,6 vient de frapper Hokkaido, au Japon. Une alerte au tsunami a été émise.
Tsunami data from: https://tsunami.gov/events/PHEB/2025/12/08/25342050/2/WEPA40/WEPA40.txt
ZCZC
WEPA40 PHEB 081509
TSUPAC
TSUNAMI MESSAGE NUMBER 2
NWS PACIFIC TSUNAMI WARNING CENTER HONOLULU HI
1507 UTC MON DEC 8 2025
...PTWC TSUNAMI THREAT MESSAGE...
**** NOTICE **** NOTICE **** NOTICE **** NOTICE **** NOTICE *****
THIS MESSAGE IS ISSUED FOR INFORMATION ONLY IN SUPPORT OF THE
UNESCO/IOC PACIFIC TSUNAMI WARNING AND MITIGATION SYSTEM AND IS
MEANT FOR NATIONAL AUTHORITIES IN EACH COUNTRY OF THAT SYSTEM.
NATIONAL AUTHORITIES WILL DETERMINE THE APPROPRIATE LEVEL OF
ALERT FOR EACH COUNTRY AND MAY ISSUE ADDITIONAL OR MORE REFINED
INFORMATION.
**** NOTICE **** NOTICE **** NOTICE **** NOTICE **** NOTICE *****
THE TSUNAMI FORECAST IS UPDATED IN THIS MESSAGE.
PRELIMINARY EARTHQUAKE PARAMETERS
---------------------------------
* MAGNITUDE 7.6
* ORIGIN TIME 1415 UTC DEC 8 2025
* COORDINATES 41.0 NORTH 142.3 EAST
* DEPTH 51 KM / 32 MILES
* LOCATION HOKKAIDO JAPAN REGION
EVALUATION
----------
* AN EARTHQUAKE WITH A PRELIMINARY MAGNITUDE OF 7.6 OCCURRED IN
THE HOKKAIDO, JAPAN REGION AT 1415 UTC ON MONDAY DECEMBER 8
2025.
* BASED ON ALL AVAILABLE DATA... HAZARDOUS TSUNAMI WAVES ARE
FORECAST FOR SOME COASTS.
TSUNAMI THREAT FORECAST...UPDATED
---------------------------------
* TSUNAMI WAVES REACHING 0.3 TO 1 METERS ABOVE THE TIDE LEVEL
ARE POSSIBLE FOR SOME COASTS OF
JAPAN.
* TSUNAMI WAVES ARE FORECAST TO BE LESS THAN 0.3 METERS ABOVE
THE TIDE LEVEL FOR THE COASTS OF
CHUUK... DPR OF KOREA... GUAM... JOHNSTON ATOLL...
KOSRAE... MARSHALL ISLANDS... MIDWAY ISLAND... NORTHERN
MARIANAS... NORTHWESTERN HAWAIIAN ISLANDS...
PHILIPPINES... POHNPEI... RUSSIA... WAKE ISLAND... AND
YAP.
* ACTUAL AMPLITUDES AT THE COAST MAY VARY FROM FORECAST
AMPLITUDES DUE TO UNCERTAINTIES IN THE FORECAST AND LOCAL
FEATURES. IN PARTICULAR MAXIMUM TSUNAMI AMPLITUDES ON ATOLLS
AND AT LOCATIONS WITH FRINGING OR BARRIER REEFS WILL LIKELY
BE MUCH SMALLER THAN THE FORECAST INDICATES.
* FOR OTHER AREAS COVERED BY THIS PRODUCT A FORECAST HAS NOT
YET BEEN COMPUTED. THE FORECAST WILL BE EXPANDED IF
NECESSARY IN SUBSEQUENT PRODUCTS.
RECOMMENDED ACTIONS
-------------------
* GOVERNMENT AGENCIES RESPONSIBLE FOR THREATENED COASTAL AREAS
SHOULD TAKE ACTION TO INFORM AND INSTRUCT ANY COASTAL
POPULATIONS AT RISK IN ACCORDANCE WITH THEIR OWN
EVALUATION... PROCEDURES AND THE LEVEL OF THREAT.
* PERSONS LOCATED IN THREATENED COASTAL AREAS SHOULD STAY ALERT
FOR INFORMATION AND FOLLOW INSTRUCTIONS FROM NATIONAL AND
LOCAL AUTHORITIES.
ESTIMATED TIMES OF ARRIVAL
--------------------------
* ESTIMATED TIMES OF ARRIVAL -ETA- OF THE INITIAL TSUNAMI WAVE
FOR PLACES WITHIN THREATENED REGIONS ARE GIVEN BELOW. ACTUAL
ARRIVAL TIMES MAY DIFFER AND THE INITIAL WAVE MAY NOT BE THE
LARGEST. A TSUNAMI IS A SERIES OF WAVES AND THE TIME BETWEEN
WAVES CAN BE FIVE MINUTES TO ONE HOUR.
LOCATION REGION COORDINATES ETA(UTC)
------------------------------------------------------------
HACHINOHE JAPAN 40.5N 141.5E 1450 12/08
KUSHIRO JAPAN 42.9N 144.3E 1501 12/08
KATSUURA JAPAN 35.1N 140.3E 1537 12/08
SAPPORO JAPAN 43.5N 141.0E 1622 12/08
NIIGATA JAPAN 38.0N 139.0E 1640 12/08
SHIMIZU JAPAN 32.8N 133.0E 1658 12/08
NOBEOKA JAPAN 32.5N 131.8E 1705 12/08
SHIMANE JAPAN 35.8N 133.0E 1739 12/08
NAGASAKI JAPAN 32.7N 129.7E 1848 12/08
POTENTIAL IMPACTS
-----------------
* A TSUNAMI IS A SERIES OF WAVES. THE TIME BETWEEN WAVE CRESTS
CAN VARY FROM 5 MINUTES TO AN HOUR. THE HAZARD MAY PERSIST
FOR MANY HOURS OR LONGER AFTER THE INITIAL WAVE.
* IMPACTS CAN VARY SIGNIFICANTLY FROM ONE SECTION OF COAST TO
THE NEXT DUE TO LOCAL BATHYMETRY AND THE SHAPE AND ELEVATION
OF THE SHORELINE.
* IMPACTS CAN ALSO VARY DEPENDING UPON THE STATE OF THE TIDE AT
THE TIME OF THE MAXIMUM TSUNAMI WAVES.
* PERSONS CAUGHT IN THE WATER OF A TSUNAMI MAY DROWN... BE
CRUSHED BY DEBRIS IN THE WATER... OR BE SWEPT OUT TO SEA.
NEXT UPDATE AND ADDITIONAL INFORMATION
--------------------------------------
* THE NEXT MESSAGE WILL BE ISSUED IN ONE HOUR... OR SOONER IF
THE SITUATION WARRANTS.
* AUTHORITATIVE INFORMATION ABOUT THE EARTHQUAKE FROM THE U.S.
GEOLOGICAL SURVEY CAN BE FOUND ON THE INTERNET AT
EARTHQUAKE.USGS.GOV.
* FURTHER INFORMATION ABOUT THIS EVENT MAY BE FOUND 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
WWW.TSUNAMI.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 WWW.TSUNAMI.GOV.
$$
NNNN
Données sur les séismes:
| Date et heure d'origine: | 2025-12-08 14:15:11 UTC |
| Date et heure d'arrivée à la station sismique Citizen: | 2025-12-08 14:28:06 UTC |
| Emplacement de la station: | Germans Sàbat, Girona, ES (EU) |
| Décalage horaire entre l'événement et l'arrivée à la gare: | 12 minutes et 55 secondes |
| Distance entre l'épicentre et la station: | 9.927,20 Km |
| Vitesse de l'onde: | 12,81 km/s => 12.809,29 m/s |
| Type de vague (selon la vitesse): | SKS |
| Type de capteur: | Géophone 4,5 Hz - 200 V/m/s |
| Fréquence d'échantillonnage (sps): | 100Hz |
| Alarmes : fréquences activées à l'arrivée de l'onde: * Par ordre de détection |
0.5-1Hz |
| Lieu d'origine: | Hokkaido, 122 km ENE of Aomori, Japan, 81 km NNE of Hachinohe, Japan |
| Coordonnées géodésiques de l'épicentre: | 📍 40.9600°N 142.1850°E |
| Profondeur (hypocentre): | 29.0 km |
| Alerte au tsunami: | Oui |
| Magnitude de l'échelle de Richter: | M7.6 |
| Magnitude de l'échelle de Mercalli modifiée MMI => DYFI (L'avez-vous ressenti ?): | VII |
| URL Données officielles USGS: | https://earthquake.usgs.gov/earthquakes/eventpage/... |
| URL Données officielles EMSC: | https://www.emsc-csem.org/Earthquake_information/e... |
| URL de données non officielle Volcano Discovery: | https://www.volcanodiscovery.com/earthquakes/quake... |