Reviewed by USGSTonga20y ago
M4.2 earthquake 22 km SSE of Pangai, Tonga
Monday, June 26, 2006, 14:56:09 UTC · 19.993°S, 174.244°W
A magnitude 4.2 earthquake struck 22 km SSE of Pangai, Tonga on Monday, June 26, 2006, 14:56:09 UTC, at a depth of 35.8 km (shallow).
- Magnitude
- 4.2
- Light · mb
- Depth
- 36 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: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
30 tons of TNT
That is about 1/500 of the Hiroshima bomb. A magnitude 5.0 releases about 16 times more energy.
Tectonic setting
106 km
from the nearest mapped plate boundary, between the Tonga and Niuafo'ou plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
36 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 lists 2 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.7 on July 14, 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 1,212 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 · 265 km NE of this epicenter
- 8.0TongaJanuary 4, 1903 · 79 km W of this epicenter
- 8.02006 Tonga EarthquakeMay 3, 2006 · 25 km SE of this epicenter
- 7.8159 km W of Pangai, TongaDecember 14, 1950 · 173 km W of this epicenter
- 7.8111 km SSE of Pangai, TongaJune 26, 1913 · 89 km SE of this epicenter
- 7.5110 km E of ‘Ohonua, TongaSeptember 8, 1948 · 142 km S of this epicenter
- 7.4103 km ESE of Neiafu, TongaFebruary 27, 1921 · 175 km NE of this epicenter
- 7.385 km ESE of Neiafu, TongaJanuary 2, 1907 · 142 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 12 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1919M8.1
Tonga Islands
30 Apr 1919 · 257 km away
Limited damage (under $1M)tsunami
- 1865M8.0
Tonga Islands
18 Nov 1865 · 95 km away
Limited damage (under $1M)tsunami
- 2006M7.9
Tonga Islands
3 May 2006 · 25 km away · intensity VII
Limited damage (under $1M)tsunami
- 1903M8.0
Tonga Islands
4 Jan 1903 · 79 km away
- 1948M7.9
Tonga Islands
8 Sep 1948 · 115 km away
tsunami
- 1902M7.8
Tonga Islands
9 Feb 1902 · 26 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.