Reviewed by USGSVanuatu77y ago
M7.1 earthquake 91 km SSE of Isangel, Vanuatu
Friday, May 26, 1950, 01:17:14 UTC · 20.253°S, 169.723°E
A magnitude 7.1 earthquake struck 91 km SSE of Isangel, Vanuatu on Friday, May 26, 1950, 01:17:14 UTC, at a depth of 50.0 km (shallow). It is the strongest earthquake within 300 km since an M7.2 on November 24, 1944.
- Magnitude
- 7.1
- Major · mw
- Depth
- 50 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- VII
- Very strong (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 200 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
607 kilotons of TNT
That is about 40 times the Hiroshima bomb. It released about 1,274 times the energy of a magnitude 5.0.
Tectonic setting
132 km
from the nearest mapped plate boundary, between the New Hebrides and Australian plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
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 200 km
USGS lists 4 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M6.9 on June 24, 1950. 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 88 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.11920 Vanuatu EarthquakeSeptember 20, 1920 · 133 km W of this epicenter
- 7.828 km ESE of Isangel, VanuatuJune 16, 1910 · 75 km N of this epicenter
- 7.663 km NW of Isangel, VanuatuOctober 14, 1913 · 155 km NW of this epicenter
- 7.6274 km ESE of Tadine, New CaledoniaMarch 16, 1928 · 244 km S of this epicenter
- 7.247 km NNW of Isangel, VanuatuNovember 24, 1944 · 137 km NW of this epicenter
- 7.2113 km SSE of Port-Vila, VanuatuMarch 22, 1925 · 208 km NW of this epicenter
- 7.1southeast of the Loyalty IslandsAugust 17, 1935 · 291 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 16 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 26 recorded deaths. The most severe:
- 1875M8.1
Loyalty Islands: Lifou Island
28 Mar 1875 · 131 km away
26 deathsSevere damage ($5–24M)tsunami
- 1901M7.9
Loyalty Islands
9 Aug 1901 · 196 km away
Moderate damage ($1–5M)tsunami
- 1920M8.1
Loyalty Islands
20 Sep 1920 · 133 km away
Limited damage (under $1M)tsunami
- 1878M7.5
Tanna Island
10 Jan 1878 · 189 km away
Limited damage (under $1M)tsunami
- 1913M8.1
Vanuatu Islands
14 Oct 1913 · 113 km away
- 1878M8.0
Vanuatu Islands
11 Feb 1878 · 189 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.