Mag. 4.9 earthquake - Gulf of Alaska, 7.3 mi northwest of Big Koniuji Island, Aleutians East County, Alaska, USA, on Thursday, 23 July 2020 at 11:08 (GMT) -
This quake was likely an aftershock of the 7.8 quake Gulf of Alaska, 31 mi east of Simeonof Island, Aleutians East County, Alaska, USA, 22 July 2020 06:12 GMT, which had occurred 1 day 5 hours earlier.
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Light magnitude 4.9 earthquake at 40 km depth
23 Jul 11:14 UTC: First to report: USGS after 5 minutes.
Jul 23 11:27: Magnitude recalculated from 5.1 to 4.9.
Hypocenter depth recalculated from 21.0 to 39.5 km.
Jul 23 11:27: Magnitude recalculated from 5.1 to 4.9.
Hypocenter depth recalculated from 21.0 to 39.5 km.
Magnitude: 4.9
Depth: 39.5 km
Epicenter latitude / longitude: 55.2309°N / 159.6341°W
(Gulf of Alaska, Alaska, United States)Nearest volcano: Stepovak Bay 2 (79 km / 49 mi)
Nearby towns and cities:
56 km (35 mi) E of Sand Point (pop: 1,060) --> See nearby quakes!
82 km (51 mi) SSW of Perryville (pop: 113) --> See nearby quakes!
126 km (79 mi) SSW of Chignik Lake (pop: 73) --> See nearby quakes!
131 km (81 mi) SE of Nelson Lagoon (pop: 52) --> See nearby quakes!
141 km (88 mi) SSW of Chignik (pop: 87) --> See nearby quakes!
172 km (107 mi) E of King Cove (pop: 1,010) --> See nearby quakes!
196 km (122 mi) E of Cold Bay (pop: 123) --> See nearby quakes!
413 km (257 mi) ENE of Akutan (pop: 1,040) --> See nearby quakes!
6122 km (3804 mi) NW of Washington DC (District of Columbia) (pop: 601,700) --> See nearby quakes!
6122 km (3804 mi) NW of Washington DC (District of Columbia) (pop: 601,700) --> See nearby quakes!
12 km (7 mi) NNW of Big Koniuji Island --> See nearby quakes!
50 km (31 mi) N of Chernabura Island --> See nearby quakes!
Primary data source: USGS (United States Geological Survey)
Estimated released energy: 1.4 x 1012 joules (392 megawatt hours, equivalent to 338 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.
| Magnitude | Depth | Location | Source |
| M 4.9 | 40 km | 56 km ESE of Sand Point, Alaska (USA) | USGS |
| M 5.0 | 36 km | Alaska Peninsula (USA) | GFZ |
| M 4.9 | 38 km | Alaska Peninsula (USA) | EMSC |
| M 5.4 | 68 km | Alaska Peninsula (USA) | BMKG |
| M 5.1 | 44 km | Alaska Peninsula (USA) | GeoAu |
User reports for this quake
User reports estimate the perceived ground shaking intensity according to the MMI (Modified Mercalli Intensity) scale.
There are no user reports for this quake yet. If you felt it be the first to report it!
Earlier earthquakes in the same area
Mag. 4.9 earthquake - Gulf of Alaska, 7.3 mi northwest of Big Koniuji Island, Aleutians East County, Alaska, USA, on Thursday, 23 July 2020 at 11:08 (GMT)
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