Very strong mag. 6.4 earthquake - North Pacific Ocean, 29 mi southeast of Tigalda Island, Aleutians East County, Alaska, USA, on Wednesday, 20 November 1957 at 12:40 (GMT)
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Very strong magnitude 6.4 earthquake at 25 km depth
Date & time: 20 Nov 1957 12:40:31 UTC
Magnitude: 6.4
Depth: 25.0 km
Epicenter latitude / longitude: 53.756°N / 164.648°W

Nearest volcano: Westdahl (85 km / 53 mi)
Nearby towns and cities:
85 km (53 mi) ESE of Akutan (pop: 1,040) --> See nearby quakes!
125 km (77 mi) E of Unalaska (pop: 4,490) --> See nearby quakes!
146 km (91 mi) SSW of False Pass (pop: 40) --> See nearby quakes!
202 km (126 mi) SW of Cold Bay (pop: 123) --> See nearby quakes!
209 km (130 mi) SW of King Cove (pop: 1,010) --> See nearby quakes!
294 km (183 mi) ENE of Nikolski (pop: 18) --> See nearby quakes!
320 km (199 mi) WSW of Sand Point (pop: 1,060) --> See nearby quakes!
333 km (207 mi) SW of Nelson Lagoon (pop: 52) --> See nearby quakes!
426 km (265 mi) WSW of Perryville (pop: 113) --> See nearby quakes!
467 km (290 mi) SW of Chignik Lake (pop: 73) --> See nearby quakes!
Primary data source: USGS (United States Geological Survey)
Estimated released energy: 2.5 x 1014 joules (69.8 gigawatt hours, equivalent to 60036 tons of TNT or 3.8 atomic bombs!) More info
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Magnitude | Depth | Location | Source |
M 6.4 | 25 km | Unimak Island region, Alaska (USA) | USGS |
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