Mag. 4.2 earthquake - Gulf of Alaska, 70 mi south of Sand Point, Aleutians East County, Alaska, USA, on Friday, 31 July 2020 at 21:19 (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 10 days earlier.
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Light magnitude 4.2 earthquake at 26 km depth
31 Jul 21:38 UTC: First to report: USGS after 19 minutes.
Jul 31 22:22: Magnitude recalculated from 4.2 to 4.1.
Hypocenter depth recalculated from 16.3 to 20.9 km.
Aug 1 01:14: Magnitude recalculated from 4.1 to 4.2.
Hypocenter depth recalculated from 20.9 to 21.6 km.
Hypocenter depth recalculated from 21.6 to 25.5 km.
Jul 31 22:22: Magnitude recalculated from 4.2 to 4.1.
Hypocenter depth recalculated from 16.3 to 20.9 km.
Aug 1 01:14: Magnitude recalculated from 4.1 to 4.2.
Hypocenter depth recalculated from 20.9 to 21.6 km.
Hypocenter depth recalculated from 21.6 to 25.5 km.
Magnitude: 4.2
Depth: 25.5 km
Epicenter latitude / longitude: 54.3742°N / 161.0262°W
(Gulf of Alaska, Alaska, United States)Nearest volcano: Dutton (125 km / 78 mi)
Nearby towns and cities:
112 km (70 mi) SSW of Sand Point (pop: 1,060) --> See nearby quakes!
113 km (70 mi) SE of King Cove (pop: 1,010) --> See nearby quakes!
141 km (88 mi) SE of Cold Bay (pop: 123) --> See nearby quakes!
163 km (101 mi) ESE of False Pass (pop: 40) --> See nearby quakes!
181 km (113 mi) S of Nelson Lagoon (pop: 52) --> See nearby quakes!
209 km (130 mi) SW of Perryville (pop: 113) --> See nearby quakes!
310 km (192 mi) E of Akutan (pop: 1,040) --> See nearby quakes!
363 km (226 mi) ENE of Unalaska (pop: 4,490) --> See nearby quakes!
6239 km (3877 mi) NW of Washington (District of Columbia) (pop: 601,700) --> See nearby quakes!
6239 km (3877 mi) NW of Washington DC (District of Columbia) (pop: 601,700) --> See nearby quakes!
91 km (57 mi) ESE of Cherni Island --> See nearby quakes!
105 km (66 mi) WSW of Chernabura Island --> See nearby quakes!
Primary data source: USGS (United States Geological Survey)
Estimated released energy: 1.3 x 1011 joules (35 megawatt hours, equivalent to 30.1 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 4.2 | 26 km | 112 km SSW of Sand Point, Alaska (USA) | USGS |
| M 4.2 | 40 km | Alaska Peninsula (USA) | EMSC |
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. 4.2 earthquake - Gulf of Alaska, 70 mi south of Sand Point, Aleutians East County, Alaska, USA, on Friday, 31 July 2020 at 21:19 (GMT)
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