Strong mag. 5.2 earthquake - Gulf of Alaska, 12 mi south of Twoheaded Island, Kodiak Island, Alaska, USA, on Wednesday, 12 April 1978 at 03:48 (GMT)

Strong mag. 5.2 earthquake - Gulf of Alaska, 12 mi south of Twoheaded Island, Kodiak Island, Alaska, USA, on Wednesday, 12 April 1978 at 03:48 (GMT)

Strong magnitude 5.2 earthquake at 23 km depth

Date & time: 12 Apr 1978 03:48:55 UTC
Magnitude: 5.2
Depth: 23.0 km
Epicenter latitude / longitude: 56.738°N / 153.637°W (Gulf of Alaska, Alaska, United States)
Nearest volcano: Unnamed 57.87°N/155.42°W (165 km / 103 mi)
Nearby towns and cities:
40 km (25 mi) SE of Akhiok (pop: 72) --> See nearby quakes!
56 km (34 mi) SSW of Old Harbor (pop: 221) --> See nearby quakes!
92 km (57 mi) SSE of Larsen Bay (pop: 88) --> See nearby quakes!
130 km (81 mi) SSW of Kodiak Station (pop: 1,300) --> See nearby quakes!
138 km (86 mi) SSW of Kodiak (pop: 6,250) --> See nearby quakes!
345 km (215 mi) SSW of Homer (pop: 5,520) --> See nearby quakes!
431 km (268 mi) SSW of Kalifornsky (pop: 7,850) --> See nearby quakes!
443 km (275 mi) SSW of Soldotna (pop: 4,540) --> See nearby quakes!
446 km (277 mi) SSW of Kenai (pop: 7,660) --> See nearby quakes!
454 km (282 mi) SSW of Sterling (pop: 5,620) --> See nearby quakes!
Primary data source: USGS (United States Geological Survey)
Estimated released energy: 4 x 1012 joules (1.11 gigawatt hours, equivalent to 951 tons of TNT) More info
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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.
5.223 kmKodiak Island region, Alaska (USA)USGS
Note: for quakes of 2012 and earlier, our database often contains only records from USGS.

User reports for this quake

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There are no user reports for this quake yet. If you felt it be the first to report it!
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Recorded aftershocks, latest first (0 quakes):
So far, no aftershocks have been registered.

Earlier earthquakes in the same area

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