Reviewed by USGSTonga48y ago
M4.4 earthquake 35 km ESE of Hihifo, Tonga
Sunday, June 18, 1978, 09:35:00 UTC · 16.080°S, 173.493°W
A magnitude 4.4 earthquake struck 35 km ESE of Hihifo, Tonga on Sunday, June 18, 1978, 09:35:00 UTC, at a depth of 33.0 km (shallow).
- Magnitude
- 4.4
- Light · mb
- 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 earthquake
In context
How big was it, and why here?
Energy released
60 tons of TNT
That is about 1/251 of the Hiroshima bomb. A magnitude 5.0 releases about 8 times more energy.
Tectonic setting
115 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
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 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 402 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 · 273 km SE of this epicenter
- 8.0The 1917 Samoa-Tonga EarthquakeJune 26, 1917 · 123 km N of this epicenter
- 7.8146 km ESE of Hihifo, TongaDecember 26, 1975 · 111 km E of this epicenter
- 7.6199 km ESE of Hihifo, TongaApril 2, 1977 · 164 km SE of this epicenter
- 7.1112 km NNE of Hihifo, TongaApril 14, 1957 · 118 km N of this epicenter
- 7.0146 km NW of Neiafu, TongaMay 22, 1972 · 249 km SW of this epicenter
- 7.0206 km SE of Hihifo, TongaJune 17, 1978 · 173 km SE of this epicenter
- 6.9127 km S of Hihifo, TongaMay 8, 1913 · 124 km SW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 5 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 2 recorded deaths. The most severe:
- 1917M8.3
Samoa Islands
26 Jun 1917 · 83 km away
2 deathsModerate damage ($1–5M)tsunami
- 1919M8.1
Tonga Islands
30 Apr 1919 · 273 km away
Limited damage (under $1M)tsunami
- 1977M7.6
Apia
2 Apr 1977 · 164 km away · intensity VI
Limited damage (under $1M)tsunami
- 1975M7.8
Samoa Islands
26 Dec 1975 · 111 km away · intensity V
tsunami
- 1957M7.5
Samoa Islands
14 Apr 1957 · 83 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.