Reviewed by USGSNew Zealand84y ago
M6.4 earthquake in Kermadec Islands, New Zealand
Monday, September 27, 1943, 22:03:44 UTC · 30.031°S, 178.004°W
A magnitude 6.4 earthquake struck in Kermadec Islands, New Zealand on Monday, September 27, 1943, 22:03:44 UTC, at a depth of 59.0 km (shallow). It is the strongest earthquake within 300 km since an M7.0 on September 14, 1943.
- Magnitude
- 6.4
- Strong · mw
- Depth
- 59 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
54 kilotons of TNT
That is about 4 times the Hiroshima bomb. It released about 114 times the energy of a magnitude 5.0.
Tectonic setting
106 km
from the nearest mapped plate boundary, between the Kermadec and Australian plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
59 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 50 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.21917 Kermadec Islands, New Zealand EarthquakeMay 1, 1917 · 183 km SE of this epicenter
- 7.5Kermadec Islands, New ZealandNovember 16, 1917 · 26 km NE of this epicenter
- 7.2Kermadec Islands, New ZealandAugust 2, 1941 · 48 km NE of this epicenter
- 7.2Kermadec Islands, New ZealandApril 17, 1919 · 61 km S of this epicenter
- 7.1Kermadec Islands, New ZealandJune 29, 1910 · 130 km SE of this epicenter
- 7.1Kermadec Islands, New ZealandSeptember 16, 1941 · 103 km N of this epicenter
- 7.0Kermadec Islands, New ZealandSeptember 14, 1943 · 28 km SE of this epicenter
- 7.0Kermadec Islands, New ZealandJune 13, 1917 · 89 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 3 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1917M8.0
Kermadec Islands
1 May 1917 · 134 km away
tsunami
- 1943M7.6
S Of
14 Sep 1943 · 97 km away
- 1917M7.5
S Of
16 Nov 1917 · 125 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.