Reviewed by USGSTonga20y ago
M4.6 earthquake 47 km SSW of Pangai, Tonga
Sunday, June 18, 2006, 18:49:25 UTC · 20.211°S, 174.524°W
A magnitude 4.6 earthquake struck 47 km SSW of Pangai, Tonga on Sunday, June 18, 2006, 18:49:25 UTC, at a depth of 50.0 km (shallow). It is the strongest earthquake within 300 km since an M4.9 on June 18, 2006.
- Magnitude
- 4.6
- Light · mb
- Depth
- 50 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
120 tons of TNT
That is about 1/126 of the Hiroshima bomb. A magnitude 5.0 releases about 4 times more energy.
Tectonic setting
91 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
50 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 3 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.9 on June 18, 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 1,211 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.0TongaJanuary 4, 1903 · 55 km NW of this epicenter
- 8.02006 Tonga EarthquakeMay 3, 2006 · 42 km E of this epicenter
- 7.8159 km W of Pangai, TongaDecember 14, 1950 · 152 km W of this epicenter
- 7.8111 km SSE of Pangai, TongaJune 26, 1913 · 91 km SE of this epicenter
- 7.5110 km E of ‘Ohonua, TongaSeptember 8, 1948 · 130 km SE of this epicenter
- 7.4103 km ESE of Neiafu, TongaFebruary 27, 1921 · 213 km NE of this epicenter
- 7.385 km ESE of Neiafu, TongaJanuary 2, 1907 · 180 km NE of this epicenter
- 7.3227 km WNW of Haveluloto, TongaApril 16, 1937 · 294 km W 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 · 295 km away
Limited damage (under $1M)tsunami
- 1865M8.0
Tonga Islands
18 Nov 1865 · 133 km away
Limited damage (under $1M)tsunami
- 2006M7.9
Tonga Islands
3 May 2006 · 42 km away · intensity VII
Limited damage (under $1M)tsunami
- 1937M8.1
Fiji Islands
16 Apr 1937 · 295 km away
- 1903M8.0
Tonga Islands
4 Jan 1903 · 55 km away
- 1948M7.9
Tonga Islands
8 Sep 1948 · 103 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.