Reviewed by USGS101y ago
M7.0 earthquake southeast of the Loyalty Islands
Wednesday, August 25, 1926, 05:44:45 UTC · 23.098°S, 172.219°E
A magnitude 7.0 earthquake struck southeast of the Loyalty Islands on Wednesday, August 25, 1926, 05:44:45 UTC, at a depth of 20.0 km (shallow). It is the strongest earthquake within 300 km since an M7.2 on November 14, 1906.
- Magnitude
- 7.0
- Major · mw
- Depth
- 20 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: 200 km aftershock search area
In context
How big was it, and why here?
Energy released
548 kilotons of TNT
That is about 36 times the Hiroshima bomb. It released about 1,148 times the energy of a magnitude 5.0.
Tectonic setting
9 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
20 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 1 M2.5+ earthquake within 200 km in the following 30 days; the largest was M6.5 on August 25, 1926. 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 23 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 · 88 km NW of this epicenter
- 7.1southeast of the Loyalty IslandsApril 14, 1906 · 128 km NW of this epicenter
- 7.0204 km E of Tadine, New CaledoniaFebruary 1, 1923 · 292 km NW of this epicenter
- 6.8southeast of the Loyalty IslandsFebruary 9, 1925 · 158 km NW of this epicenter
- 6.8southeast of the Loyalty IslandsMarch 10, 1906 · 148 km N of this epicenter
- 6.8southeast of the Loyalty IslandsJanuary 30, 1910 · 192 km SW of this epicenter
- 6.7southeast of the Loyalty IslandsJuly 17, 1905 · 37 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 1 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1901M7.9
Loyalty Islands
9 Aug 1901 · 259 km away
Moderate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.