Reviewed by USGSVanuatu88y ago
M7.1 earthquake 48 km SSW of Isangel, Vanuatu
Wednesday, April 5, 1939, 16:42:43 UTC · 19.924°S, 169.055°E
A magnitude 7.1 earthquake struck 48 km SSW of Isangel, Vanuatu on Wednesday, April 5, 1939, 16:42:43 UTC, at a depth of 30.0 km (shallow). It is the strongest earthquake within 300 km since an M7.1 on January 24, 1927.
- Magnitude
- 7.1
- Major · mw
- Depth
- 30 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- VI
- Strong (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
587 kilotons of TNT
That is about 39 times the Hiroshima bomb. It released about 1,230 times the energy of a magnitude 5.0.
Tectonic setting
87 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
30 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 has not published any M2.5+ earthquake within 200 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 55 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 · 61 km W of this epicenter
- 7.828 km ESE of Isangel, VanuatuJune 16, 1910 · 63 km NE of this epicenter
- 7.663 km NW of Isangel, VanuatuOctober 14, 1913 · 95 km N of this epicenter
- 7.2113 km SSE of Port-Vila, VanuatuMarch 22, 1925 · 142 km N of this epicenter
- 7.1175 km SE of Isangel, VanuatuMarch 30, 1910 · 166 km SE of this epicenter
- 7.184 km SW of Port-Vila, VanuatuJanuary 24, 1927 · 228 km NW of this epicenter
- 7.072 km SW of Isangel, VanuatuMay 30, 1938 · 30 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 18 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 · 59 km away
26 deathsSevere damage ($5–24M)tsunami
- 1901M7.9
Loyalty Islands
9 Aug 1901 · 251 km away
Moderate damage ($1–5M)tsunami
- 1920M8.1
Loyalty Islands
20 Sep 1920 · 61 km away
Limited damage (under $1M)tsunami
- 1878M7.5
Tanna Island
10 Jan 1878 · 118 km away
Limited damage (under $1M)tsunami
- 1913M8.1
Vanuatu Islands
14 Oct 1913 · 47 km away
- 1878M8.0
Vanuatu Islands
11 Feb 1878 · 118 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.