QuakeScout
Magnitude4.3

Reviewed by USGSTonga2y ago

M4.3 earthquake 102 km NNE of Hihifo, Tonga

Thursday, October 19, 2023, 06:43:17 UTC · 15.060°S, 173.548°W

A magnitude 4.3 earthquake struck 102 km NNE of Hihifo, Tonga on Thursday, October 19, 2023, 06:43:17 UTC, at a depth of 10.0 km (shallow).

Magnitude
4.3
Light · mb
Depth
10 km
Shallow
Felt reports
0
Did You Feel It?
Est. shaking
—
No ShakeMap
PAGER alert
None
Not issued
Tsunami
No flag
USGS feed

Outlined circle: this earthquake

In context

How big was it, and why here?

Energy released

43 tons of TNT

That is about 1/354 of the Hiroshima bomb. A magnitude 5.0 releases about 11 times more energy.

Tectonic setting

50 km

from the nearest mapped plate boundary, between the Tonga and Pacific plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.

Depth: shallow

10 km

Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.

Did You Feel It?

Where it was felt

No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.

I felt it — report to USGS ↗

USGS PAGER estimate

Who was exposed to shaking

USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.

After the main event

Aftershocks within 50 km

USGS has not published any M2.5+ earthquake within 50 km in the 30 days after this event.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 1,752 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

  1. 8.12009 Samoa EarthquakeSeptember 29, 2009 · 163 km E of this epicenter
  2. 8.0The 1917 Samoa-Tonga EarthquakeJune 26, 1917 · 31 km E of this epicenter
  3. 7.8146 km ESE of Hihifo, TongaDecember 26, 1975 · 177 km SE of this epicenter
  4. 7.7133 km NE of Hihifo, TongaSeptember 1, 1981 · 51 km E of this epicenter
  5. 7.682 km WNW of Hihifo, TongaMay 10, 2023 · 119 km SW of this epicenter
  6. 7.6199 km ESE of Hihifo, TongaApril 2, 1977 · 239 km SE of this epicenter
  7. 7.488 km NNE of Hihifo, TongaApril 7, 1995 · 16 km S of this epicenter
  8. 7.2117 km SSW of Hihifo, TongaJanuary 8, 2000 · 220 km S of this epicenter

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 9 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 194 recorded deaths. The most severe:

  1. 2009M8.1

    Samoa Islands

    29 Sep 2009 · 163 km away

    192 deaths$285 million damagetsunami

  2. 1917M8.3

    Samoa Islands

    26 Jun 1917 · 76 km away

    2 deathsModerate damage ($1–5M)tsunami

  3. 1981M7.7

    Apia; American Samoa: Pago Pago

    1 Sep 1981 · 51 km away · intensity VI

    Limited damage (under $1M)tsunami

  4. 1977M7.6

    Apia

    2 Apr 1977 · 239 km away · intensity VI

    Limited damage (under $1M)tsunami

  5. 1975M7.8

    Samoa Islands

    26 Dec 1975 · 177 km away · intensity V

    tsunami

  6. 2023M7.6

    Hihifo

    10 May 2023 · 129 km away

NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.

Nearby trackers

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