Reviewed by USGSVanuatu41y ago
M7.1 earthquake 210 km SSE of Isangel, Vanuatu
Wednesday, January 15, 1986, 20:17:42 UTC · 21.277°S, 170.102°E
A magnitude 7.1 earthquake struck 210 km SSE of Isangel, Vanuatu on Wednesday, January 15, 1986, 20:17:42 UTC, at a depth of 150.0 km (intermediate). It is the strongest earthquake within 300 km since an M7.1 on November 15, 1984.
- Magnitude
- 7.1
- Major · mw
- Depth
- 150 km
- Intermediate
- 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: 200 km aftershock search area
In context
How big was it, and why here?
Energy released
674 kilotons of TNT
That is about 45 times the Hiroshima bomb. It released about 1,413 times the energy of a magnitude 5.0.
Tectonic setting
103 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: intermediate
150 km
Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.
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 3 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M5.5 on February 10, 1986. 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 582 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 · 222 km NW of this epicenter
- 7.828 km ESE of Isangel, VanuatuJune 16, 1910 · 195 km N of this epicenter
- 7.663 km NW of Isangel, VanuatuOctober 14, 1913 · 274 km NW of this epicenter
- 7.6274 km ESE of Tadine, New CaledoniaMarch 16, 1928 · 124 km S of this epicenter
- 7.2southeast of the Loyalty IslandsNovember 14, 1906 · 210 km SE of this epicenter
- 7.247 km NNW of Isangel, VanuatuNovember 24, 1944 · 258 km N of this epicenter
- 7.262 km NE of Isangel, VanuatuJuly 2, 1953 · 248 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 12 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 · 219 km away
26 deathsSevere damage ($5–24M)tsunami
- 1901M7.9
Loyalty Islands
9 Aug 1901 · 81 km away
Moderate damage ($1–5M)tsunami
- 1920M8.1
Loyalty Islands
20 Sep 1920 · 222 km away
Limited damage (under $1M)tsunami
- 1913M8.1
Vanuatu Islands
14 Oct 1913 · 229 km away
- 1910M7.9
Vanuatu Islands
16 Jun 1910 · 261 km away
- 1910M7.5
Vanuatu Islands
1 Jun 1910 · 183 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.