Reviewed by USGSTonga20y ago
M5.0 earthquake 66 km ESE of Neiafu, Tonga
Wednesday, July 26, 2006, 03:26:21 UTC · 18.874°S, 173.397°W
A magnitude 5.0 earthquake struck 66 km ESE of Neiafu, Tonga on Wednesday, July 26, 2006, 03:26:21 UTC, at a depth of 32.5 km (shallow). It is the strongest earthquake within 300 km since an M5.2 on July 26, 2006.
- Magnitude
- 5.0
- Moderate · mwc
- 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: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
477 tons of TNT
That is about 1/32 of the Hiroshima bomb. Each whole step in magnitude is about 32 times more energy.
Tectonic setting
59 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
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 75 km
USGS lists 4 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M5.2 on August 1, 2006. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1,206 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.11919 Tonga EarthquakeApril 30, 1919 · 118 km NE of this epicenter
- 8.0TongaJanuary 4, 1903 · 210 km SW of this epicenter
- 8.02006 Tonga EarthquakeMay 3, 2006 · 165 km SW of this epicenter
- 7.8159 km W of Pangai, TongaDecember 14, 1950 · 276 km W of this epicenter
- 7.8111 km SSE of Pangai, TongaJune 26, 1913 · 205 km S of this epicenter
- 7.6199 km ESE of Hihifo, TongaApril 2, 1977 · 279 km NE of this epicenter
- 7.5110 km E of ‘Ohonua, TongaSeptember 8, 1948 · 266 km S of this epicenter
- 7.4103 km ESE of Neiafu, TongaFebruary 27, 1921 · 38 km E of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 13 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1919M8.1
Tonga Islands
30 Apr 1919 · 110 km away
Limited damage (under $1M)tsunami
- 1865M8.0
Tonga Islands
18 Nov 1865 · 70 km away
Limited damage (under $1M)tsunami
- 2006M7.9
Tonga Islands
3 May 2006 · 165 km away · intensity VII
Limited damage (under $1M)tsunami
- 1977M7.6
Apia
2 Apr 1977 · 279 km away · intensity VI
Limited damage (under $1M)tsunami
- 1903M8.0
Tonga Islands
4 Jan 1903 · 210 km away
- 1948M7.9
Tonga Islands
8 Sep 1948 · 245 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.