Reviewed by USGS31y ago
M4.2 earthquake southeast of the Loyalty Islands
Tuesday, November 21, 1995, 16:09:34 UTC · 23.484°S, 170.347°E
A magnitude 4.2 earthquake struck southeast of the Loyalty Islands on Tuesday, November 21, 1995, 16:09:34 UTC, at a depth of 33.0 km (shallow).
- Magnitude
- 4.2
- 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 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
74 km
from the nearest mapped plate boundary, between the New Hebrides and Australian 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 50 km
USGS lists 2 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.7 on November 22, 1995. 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 475 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.7249 km E of Vao, New CaledoniaMay 16, 1995 · 70 km NW of this epicenter
- 7.6274 km ESE of Tadine, New CaledoniaMarch 16, 1928 · 125 km N of this epicenter
- 7.2southeast of the Loyalty IslandsNovember 14, 1906 · 167 km NE of this epicenter
- 7.2207 km E of Tadine, New CaledoniaOctober 25, 1980 · 184 km N of this epicenter
- 7.1southeast of the Loyalty IslandsAugust 17, 1935 · 174 km NE of this epicenter
- 7.1southeast of the Loyalty IslandsApril 14, 1906 · 166 km NE of this epicenter
- 7.1210 km SSE of Isangel, VanuatuJanuary 15, 1986 · 247 km N 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. The most severe:
- 1901M7.9
Loyalty Islands
9 Aug 1901 · 169 km away
Moderate damage ($1–5M)tsunami
- 1995M7.7
Noumea; Vanuatu: Port-Vila
16 May 1995 · 70 km away · intensity III
tsunami
- 1928M7.5
Loyalty Islands
16 Mar 1928 · 166 km away
- 1943M7.5
Loyalty Islands
14 Sep 1943 · 178 km away
- 1944M7.5
Loyalty Islands
5 Oct 1944 · 201 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.