Reviewed by USGS39y ago
M6.5 earthquake in Vanuatu region
Wednesday, June 24, 1987, 03:30:30 UTC · 21.179°S, 173.581°E
A magnitude 6.5 earthquake struck in Vanuatu region on Wednesday, June 24, 1987, 03:30:30 UTC, at a depth of 33.0 km (shallow). It is the strongest earthquake within 300 km since an M7.1 on November 15, 1984.
- Magnitude
- 6.5
- Strong · mw
- 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: 100 km aftershock search area
In context
How big was it, and why here?
Energy released
85 kilotons of TNT
That is about 6 times the Hiroshima bomb. It released about 178 times the energy of a magnitude 5.0.
Tectonic setting
4 km
from the nearest mapped plate boundary, between the Conway Reef and New Hebrides 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 100 km
USGS lists 3 M2.5+ earthquakes within 100 km in the following 30 days; the largest was M5.8 on June 24, 1987. 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 149 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.2southeast of the Loyalty IslandsNovember 14, 1906 · 253 km SW of this epicenter
- 7.1southeast of the Loyalty IslandsAugust 17, 1935 · 252 km SW of this epicenter
- 7.1southeast of the Loyalty IslandsApril 14, 1906 · 264 km SW of this epicenter
- 7.1southeast of the Loyalty IslandsNovember 15, 1984 · 288 km W of this epicenter
- 7.0southeast of the Loyalty IslandsAugust 25, 1926 · 255 km SW of this epicenter
- 7.0southeast of the Loyalty IslandsOctober 5, 1944 · 218 km SW of this epicenter
- 7.0southeast of the Loyalty IslandsJuly 6, 1981 · 227 km SW of this epicenter
- 6.8southeast of the Loyalty IslandsMarch 10, 1906 · 210 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 2 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1943M7.5
Loyalty Islands
14 Sep 1943 · 282 km away
- 1944M7.5
Loyalty Islands
5 Oct 1944 · 220 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.