Reviewed by USGS68y ago
M6.8 earthquake in Kermadec Islands region
Tuesday, September 15, 1959, 05:59:48 UTC · 28.572°S, 176.778°W
A magnitude 6.8 earthquake struck in Kermadec Islands region on Tuesday, September 15, 1959, 05:59:48 UTC, at a depth of 35.0 km (shallow). It is the strongest earthquake within 300 km since an M7.3 on September 14, 1959.
- Magnitude
- 6.8
- Strong · mw
- Depth
- 35 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
239 kilotons of TNT
That is about 16 times the Hiroshima bomb. It released about 501 times the energy of a magnitude 5.0.
Tectonic setting
77 km
from the nearest mapped plate boundary, between the Kermadec and Pacific plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
35 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 5 M2.5+ earthquakes within 100 km in the following 30 days; the largest was M6.4 on September 29, 1959. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 6.4Kermadec Islands region67y ago · 25 km S of this epicenter
- 5.9Kermadec Islands region68y ago · 69 km SE of this epicenter
- 6.2Kermadec Islands region68y ago · 27 km SE of this epicenter
- 5.6Kermadec Islands region68y ago · 47 km S of this epicenter
- 5.7Kermadec Islands, New Zealand68y ago · 81 km S of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 92 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 · 292 km S of this epicenter
- 7.5Kermadec Islands regionFebruary 27, 1955 · 118 km E of this epicenter
- 7.5Kermadec Islands, New ZealandNovember 16, 1917 · 175 km SW of this epicenter
- 7.3Kermadec Islands regionSeptember 14, 1959 · 52 km SW of this epicenter
- 7.2Kermadec Islands, New ZealandAugust 2, 1941 · 156 km SW of this epicenter
- 7.2Kermadec Islands, New ZealandApril 17, 1919 · 252 km SW of this epicenter
- 7.1Kermadec Islands, New ZealandJune 29, 1910 · 261 km S of this epicenter
- 7.1Kermadec Islands, New ZealandSeptember 16, 1941 · 121 km SW 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 · 73 km away
tsunami
- 1955M7.8
Kermadec Islands
27 Feb 1955 · 140 km away
- 1959M7.7
Kermadec Islands
14 Sep 1959 · 23 km away
- 1943M7.6
S Of
14 Sep 1943 · 160 km away
- 1917M7.5
S Of
16 Nov 1917 · 85 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.