Moderate mag. 5.5 earthquake - Gulf of Alaska, 12 mi northeast of Big Koniuji Island, Aleutians East County, Alaska, USA, on Wednesday, 22 July 2020 at 21:39 (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 15 hours earlier.
Moderate mag. 5.5 earthquake  - Gulf of Alaska, 12 mi northeast of Big Koniuji Island, Aleutians East County, Alaska, USA, on Wednesday, 22 July 2020 at 21:39 (GMT)

Moderate magnitude 5.5 earthquake at 35 km depth

22 Jul 21:46 UTC: First to report: USGS after 6 minutes.
Jul 22 21:57: Magnitude recalculated from 5.2 to 5.5.
Hypocenter depth recalculated from 51.0 to 39.1 km.
Hypocenter depth recalculated from 39.1 to 34.6 km.
Date & time: 22 Jul 2020 21:39:58 UTC -
Magnitude: 5.5
Depth: 34.6 km
Epicenter latitude / longitude: 55.2191°N / 159.2945°W (Gulf of Alaska, Alaska, United States)
Nearest volcano: Stepovak Bay 2 (87 km / 54 mi)
Nearby towns and cities:
77 km (48 mi) E of Sand Point (pop: 1,060) --> See nearby quakes!
78 km (48 mi) S of Perryville (pop: 113) --> See nearby quakes!
120 km (75 mi) SSW of Chignik Lake (pop: 73) --> See nearby quakes!
130 km (81 mi) SSW of Chignik Lagoon (pop: 78) --> See nearby quakes!
148 km (92 mi) SE of Nelson Lagoon (pop: 52) --> See nearby quakes!
193 km (120 mi) E of King Cove (pop: 1,010) --> See nearby quakes!
434 km (270 mi) ENE of Akutan (pop: 1,040) --> See nearby quakes!
510 km (317 mi) WSW of Kodiak (pop: 6,250) --> See nearby quakes!
6102 km (3792 mi) NW of Washington DC (District of Columbia) (pop: 601,700) --> See nearby quakes!
6102 km (3792 mi) NW of Washington DC (District of Columbia) (pop: 601,700) --> See nearby quakes!
19 km (12 mi) ENE of Big Koniuji Island --> See nearby quakes!
432 km (269 mi) WSW of Kodiak Island (pop: 13,600) --> See nearby quakes!
Primary data source: USGS (United States Geological Survey)
Estimated released energy: 1.1 x 1013 joules (3.12 gigawatt hours, equivalent to 2682 tons of TNT or 0.2 atomic bombs!) 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.
MagnitudeDepthLocationSource
M 5.535 kmAlaska Peninsula (USA)USGS
M 5.538 kmAlaska Peninsula (USA)GFZ
M 5.546 kmAlaska Peninsula (USA)EMSC
M 5.645 kmAlaska Peninsula (USA)GeoAu
M 5.823 kmAlaska Peninsula (USA)BMKG

User reports for this quake (2)

User reports estimate the perceived ground shaking intensity according to the MMI (Modified Mercalli Intensity) scale.
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Chignik Lake / Weak shaking (MMI III)
Chignik Lake / Moderate shaking (MMI V) : Sudden shake was quick but hit hard
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Earlier earthquakes in the same area since 1900

Moderate mag. 5.5 earthquake - Gulf of Alaska, 12 mi northeast of Big Koniuji Island, Aleutians East County, Alaska, USA, on Wednesday, 22 July 2020 at 21:39 (GMT)

Map of earlier quakes

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