Moderate mag. 4.5 earthquake - North Pacific Ocean, 35 km west of Muroran, Hokkaido, Japan, on Friday, 16 Apr 2021 5:47 am (GMT +9) -
Moderate magnitude 4.5 earthquake at 16 km depth
15 Apr 20:56 UTC: First to report: NIED after 8 minutes.
Update Thu, 15 Apr 2021, 21:00Moderate magnitude 4.5 earthquake 35 km west of Muroran, Japan
4.5 quake 16 Apr 5:47 am (GMT +9)
A shallow magnitude 4.5 earthquake was reported early morning near Muroran, Muroran-shi, Hokkaido, Japan.
According to Japan's National Research Institute for Earth Science and Disaster Resilience (NIED), the quake hit on Friday 16 April 2021 at 5:47 am local time at a shallow depth of 16.1 km. Shallow earthquakes are felt more strongly than deeper ones as they are closer to the surface. The exact magnitude, epicenter, and depth of the quake might be revised within the next few hours or minutes as seismologists review data and refine their calculations, or as other agencies issue their report.
Based on the preliminary seismic data, the quake should not have caused any significant damage, but was probably felt by many people as light vibration in the area of the epicenter.
Weak shaking might have been felt in Date (pop. 35,300) located 31 km from the epicenter, Muroran (pop. 96,200) 35 km away, Honchō (pop. 30,000) 47 km away, Kamiiso (pop. 38,100) 55 km away, and Hakodate (pop. 275,700) 61 km away.
Other towns or cities near the epicenter where the quake might have been felt as very weak shaking include Shiraoi (pop. 20,800) located 70 km from the epicenter, Iwanai (pop. 15,600) 74 km away, Tomakomai (pop. 174,800) 93 km away, and Sapporo (pop. 1,883,000) 106 km away.
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Date & time: 15 Apr 2021 20:47:52 UTC -
Local time at epicenter:
Friday, 16 Apr 2021 5:47 am (GMT +9)
Depth: 16.1 km
Epicenter latitude / longitude: 42.307°N / 140.565°E
(North Pacific Ocean
Nearest volcano: Nigorigawa
(23 km / 14 mi)
Nearby towns and cities:31 km (19 mi) SW of Date
(pop: 35,300) --> See nearby quakes!35 km (22 mi) W of Muroran
(pop: 96,200) --> See nearby quakes!47 km (29 mi) NNW of Honchō (Kameda-gun)
(pop: 30,000) --> See nearby quakes!55 km (34 mi) N of Kamiiso
(pop: 38,100) --> See nearby quakes!61 km (38 mi) NNW of Hakodate
(pop: 275,700) --> See nearby quakes!70 km (43 mi) WSW of Shiraoi
(pop: 20,800) --> See nearby quakes!74 km (46 mi) S of Iwanai
(pop: 15,600) --> See nearby quakes!93 km (58 mi) WSW of Tomakomai
(pop: 174,800) --> See nearby quakes!106 km (66 mi) SW of Sapporo
(pop: 1,883,000) --> See nearby quakes!740 km (460 mi) N of Tokyo
(pop: 8,336,600) --> See nearby quakes!92 km (57 mi) E of Okushiri Island
(pop: 3,340) --> See nearby quakes!
Weather at epicenter at time of quake:
Overcast Clouds 5.7°C
(42 F), humidity: 81%, wind: 2 m/s (4 kts) from ESE
Primary data source: NIED
(National Research Institute for Earth Science and Disaster Resilience)
Estimated released energy: 3.5 x 1011
joules (98.6 megawatt hours, equivalent to 84.8 tons of TNT) More info
Data for the same earthquake reported by different agencies
Info: The more agencies report about the same quake and post similar data, the more confidence you can have in the data. It takes normally up to a few hours until earthquake parameters are calculated with near-optimum precision.
|4.5||16 km||UCHIURA BAY REGION, Japan||NIED|
|4.6||61 km||Hokkaido, Japan Region||GFZ|
|4.6||60 km||HOKKAIDO, JAPAN REGION||EMSC|
User reports for this quake (4)
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Niseko / Light shaking (MMI IV) / rattling, vibrating / 1-2 s : Woke up to bed shaking | One user found this interesting.
61.5 km N of epicenter [Map] / Weak shaking (MMI III) / single lateral shake / very short
Abuta Gun (63.6 km N of epicenter) [Map] / Light shaking (MMI IV) / rattling, vibrating / 2-5 s
Rankoshi / Light shaking (MMI IV) / horizontal (sideways) swinging / 10-15 s
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