Magnitude6.3

Reviewed by USGSTonga27y ago

M6.3 earthquake 147 km S of Hihifo, Tonga

Wednesday, January 26, 2000, 13:26:50 UTC · 17.272°S, 174.002°W

A magnitude 6.3 earthquake struck 147 km S of Hihifo, Tonga on Wednesday, January 26, 2000, 13:26:50 UTC, at a depth of 33.0 km (shallow). It is the strongest earthquake within 300 km since an M7.2 on January 8, 2000.

Magnitude
6.3
Strong · mwb
Depth
33 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 earthquakeDashed circle: 100 km aftershock search area

In context

How big was it, and why here?

Energy released

43 kilotons of TNT

That is about 3 times the Hiroshima bomb. It released about 89 times the energy of a magnitude 5.0.

Tectonic setting

59 km

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

Depth: shallow

33 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 100 km

USGS lists 1 M2.5+ earthquake within 100 km in the following 30 days; the largest was M4.6 on February 12, 2000. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M5M61h6h1d3d7d14d30dMainshock M6.3
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 4.6148 km NNE of Neiafu, Tonga27y ago · 55 km E of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 1,290 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 11 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 2 recorded deaths. The most severe:

  1. 1917M8.3

    Samoa Islands

    26 Jun 1917 · 224 km away

    2 deathsModerate damage ($1–5M)tsunami

  2. 1919M8.1

    Tonga Islands

    30 Apr 1919 · 198 km away

    Limited damage (under $1M)tsunami

  3. 1865M8.0

    Tonga Islands

    18 Nov 1865 · 253 km away

    Limited damage (under $1M)tsunami

  4. 1981M7.7

    Apia; American Samoa: Pago Pago

    1 Sep 1981 · 275 km away · intensity VI

    Limited damage (under $1M)tsunami

  5. 1977M7.6

    Apia

    2 Apr 1977 · 213 km away · intensity VI

    Limited damage (under $1M)tsunami

  6. 1975M7.8

    Samoa Islands

    26 Dec 1975 · 198 km away · intensity V

    tsunami

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

Nearby trackers

Closest city pages