Moderate mag. 5.8 earthquake - Tonga: South of Fiji Islands on Tuesday, 17 August 2021 at 17:24 (GMT) - information

Moderate mag. 5.8 earthquake - South Pacific Ocean, 291 km southwest of Nukalofa, Nuku'alofa, Tongatapu, on Wednesday, Aug 18, 2021 at 6:24 am (GMT +13)

Moderate mag. 5.8 earthquake - South Pacific Ocean, 291 km southwest of Nukalofa, Nuku\'alofa, Tongatapu, on Wednesday, Aug 18, 2021 at 6:24 am (GMT +13) Moderate mag. 5.8 earthquake - South Pacific Ocean, 291 km southwest of Nukalofa, Nuku\'alofa, Tongatapu, on Wednesday, Aug 18, 2021 at 6:24 am (GMT +13)

Moderate magnitude 5.8 earthquake at 184 km depth

17 Aug 17:34 UTC: First to report: GFZ after 10 minutes.
17 Aug 17:36: Magnitude recalculated from 5.9 to 6.0. Hypocenter depth recalculated from 185.0 to 184.0 km (from 115 to 114 mi). Epicenter location corrected by 7.2 km (4.4 mi) towards W.
17 Aug 18:08: Magnitude recalculated from 6.0 to 5.8.

Earthquake details

Date & timeAug 17, 2021 17:24:52 UTC -
Local time at epicenterWednesday, Aug 18, 2021 at 6:24 am (GMT +13)
Depth184.0 km
Epicenter latitude / longitude23.12°S / 177.04°W (South Pacific Ocean, Tonga)
Antipode23.12°N / 2.96°E
Shaking intensityLight shaking near epicenter
Felt0 reports
Primary data sourceGFZ (German Research Centre for Geosciences)
Nearest volcanoUnnamed 24.8°S/177.02°W (187 km / 116 mi)
Nearby towns and cities289 km (179 mi) SW of Haveluloto (pop: 3,420) | Show on map | Quakes nearby
291 km (181 mi) SW of Nukalofa (Nuku'alofa) (pop: 22,400) | Show on map | Quakes nearby
291 km (181 mi) SW of Nuku‘alofa (pop: 22,400) | Show on map | Quakes nearby
293 km (182 mi) SW of ‘Ohonua (Ohonua) (pop: 1,240) | Show on map | Quakes nearby
300 km (187 mi) SW of Kolonga (pop: 1,100) | Show on map | Quakes nearby
461 km (286 mi) SW of Bangai (Pangai) (pop: 1,740) | Show on map | Quakes nearby
289 km (179 mi) SW of Amsterdam Island (pop: 75,000) | Show on map | Quakes nearby
Weather at epicenter at time of quakeLight Rain 21°C (70 F), humidity: 79%, wind: 8 m/s (16 kts) from E
Estimated seismic energy released3.2 x 1013 joules (8.78 gigawatt hours, equivalent to 7558 tons of TNT or 0.5 atomic bombs!) | about seismic energy
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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.
5.8184 kmTonga: South of Fiji IslandsGFZ
5.8182 kmTonga: South of Fiji IslandsBMKG
5.7171 kmTonga: Near North ShoreRENASS
5.8157 km285 Km SW of Vaini, TongaUSGS
5.8171 kmTonga: South of Fiji IslandsGeoAu

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.
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Recorded aftershocks, latest first (2 quakes)

Date and timeMag
Sep 17, 2021 16:42
47 weeks ago

151 km
South Pacific Ocean, 252 km SW of Nukalofa, Nuku'alofa, TongatapuMore
Aug 19, 2021 10:24
51 weeks ago

180 km
South Pacific Ocean, TongaMore

Earlier earthquakes in the same area

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