Reviewed by USGSNew Zealand64y ago
M6.5 earthquake in Kermadec Islands, New Zealand
Tuesday, March 26, 1963, 13:24:59 UTC · 29.979°S, 178.033°W
A magnitude 6.5 earthquake struck in Kermadec Islands, New Zealand on Tuesday, March 26, 1963, 13:24:59 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.3 on March 26, 1963.
- Magnitude
- 6.5
- Strong · mw
- Depth
- 15 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
102 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
15 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 4 M2.5+ earthquakes within 100 km in the following 30 days; the largest was M6.6 on March 31, 1963. 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 126 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 · 189 km SE of this epicenter
- 7.5Kermadec Islands regionFebruary 27, 1955 · 299 km NE of this epicenter
- 7.5Kermadec Islands, New ZealandNovember 16, 1917 · 24 km NE of this epicenter
- 7.3Kermadec Islands regionSeptember 14, 1959 · 150 km NE of this epicenter
- 7.3Kermadec Islands, New ZealandMarch 26, 1963 · 35 km E of this epicenter
- 7.2Kermadec Islands, New ZealandAugust 2, 1941 · 47 km NE of this epicenter
- 7.2Kermadec Islands, New ZealandApril 17, 1919 · 67 km S of this epicenter
- 7.1Kermadec Islands, New ZealandJune 29, 1910 · 137 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 5 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1917M8.0
Kermadec Islands
1 May 1917 · 132 km away
tsunami
- 1959M7.7
Kermadec Islands
14 Sep 1959 · 193 km away
- 1943M7.6
S Of
14 Sep 1943 · 100 km away
- 1917M7.5
S Of
16 Nov 1917 · 120 km away
tsunami
- 1961M7.5
Kermadec Islands
7 Mar 1961 · 294 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.