Strong mag. 5.4 earthquake - Gulf of Alaska, 64 mi south of Sand Point, Aleutians East County, Alaska, USA, on 2018-07-20 20:58:39 -11:00

This quake was likely an aftershock of the 6.0 quake Gulf of Alaska, 62 mi south of Sand Point, Aleutians East County, Alaska, USA, 2018-07-19 03:16:26 -11:00, which had occurred 1 day 18 hours earlier.
Strong mag. 5.4 earthquake - Gulf of Alaska, 64 mi south of Sand Point, Aleutians East County, Alaska, USA, on 2018-07-20 20:58:39 -11:00

Strong magnitude 5.4 earthquake at 10 km depth

21 Jul 08:06 UTC: First to report: USGS after 7 minutes.
Jul 21 08:16: Magnitude recalculated from 5.2 to 5.4.
Hypocenter depth recalculated from 54.0 to 9.9 km.
Date & time: 21 Jul 2018 07:58:39 UTC
Local time at epicenter: 2018-07-20 20:58:39 -11:00
Magnitude: 5.4
Depth: 9.9 km
Epicenter latitude / longitude: 54.4325°N / 160.894°W (Gulf of Alaska, Alaska, United States)
Nearest volcano: Dutton (122 km / 76 mi)
Nearby towns and cities:
104 km (64 mi) SSW of Sand Point (pop: 1,060) --> See nearby quakes!
115 km (72 mi) SE of King Cove (pop: 1,010) --> See nearby quakes!
144 km (89 mi) SE of Cold Bay (pop: 123) --> See nearby quakes!
169 km (105 mi) ESE of False Pass (pop: 40) --> See nearby quakes!
176 km (109 mi) S of Nelson Lagoon (pop: 52) --> See nearby quakes!
198 km (123 mi) SW of Perryville (pop: 113) --> See nearby quakes!
243 km (151 mi) SW of Chignik Lake (pop: 73) --> See nearby quakes!
257 km (159 mi) SW of Chignik Lagoon (pop: 78) --> See nearby quakes!
319 km (198 mi) E of Akutan (pop: 1,040) --> See nearby quakes!
372 km (231 mi) ENE of Unalaska (pop: 4,490) --> See nearby quakes!
Primary data source: USGS (United States Geological Survey)
Estimated released energy: 7.9 x 1012 joules (2.21 gigawatt hours, equivalent to 1898 tons of TNT or 0.1 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 5.49.9 km- 94km WSW of Chernabura Island, AlaskaUSGS
M 5.010 kmAlaska PeninsulaGFZ
M 5.420 kmALASKA PENINSULAEMSC
M 5.439 kmAlaska PeninsulaGeoAu

User reports for this quake (1)

User reports estimate the perceived ground shaking intensity according to the MMI (Modified Mercalli Intensity) scale.
198.2 km NNE of epicenter [Map] / Light shaking (MMI IV) (reported through our app)
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Earlier earthquakes in the same area since 1900


Map of earlier quakes

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