Reviewed by USGSNew Zealand region88y ago
M6.1 earthquake in Auckland Islands, New Zealand region
Sunday, September 17, 1939, 19:20:19 UTC · 50.241°S, 163.747°E
A magnitude 6.1 earthquake struck in Auckland Islands, New Zealand region on Sunday, September 17, 1939, 19:20:19 UTC, at a depth of 10.0 km (shallow). It is the strongest earthquake within 300 km since an M6.5 on February 22, 1936.
- Magnitude
- 6.1
- Strong · mw
- Depth
- 10 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 earthquake
In context
How big was it, and why here?
Energy released
20 kilotons of TNT
That is about the energy of the Hiroshima bomb. It released about 42 times the energy of a magnitude 5.0.
Tectonic setting
40 km
from the nearest mapped plate boundary, between the Pacific and Australian plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
10 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 has not published any M2.5+ earthquake within 100 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 6 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.0Auckland Islands, New Zealand regionFebruary 22, 1936 · 125 km N of this epicenter
- 6.7Auckland Islands, New Zealand regionNovember 3, 1918 · 73 km N of this epicenter
- 6.5248 km SW of Bluff, New ZealandFebruary 15, 1922 · 281 km NE of this epicenter
- 6.5off the west coast of the South Island of New ZealandFebruary 22, 1936 · 145 km N of this epicenter
- 6.2Auckland Islands, New Zealand regionAugust 13, 1932 · 133 km NE of this epicenter
- 6.0Auckland Islands, New Zealand regionJuly 23, 1928 · 67 km NW 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:
- 1926M7.9
Macquarie Island: North Of
3 Oct 1926 · 241 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.