Reviewed by USGS99y ago
M6.7 earthquake in Kermadec Islands region
Wednesday, December 12, 1928, 20:19:49 UTC · 28.186°S, 176.275°W
A magnitude 6.7 earthquake struck in Kermadec Islands region on Wednesday, December 12, 1928, 20:19:49 UTC, at a depth of 30.0 km (shallow). It is the strongest earthquake within 300 km since an M7.5 on November 16, 1917.
- Magnitude
- 6.7
- Strong · mw
- Depth
- 30 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
175 kilotons of TNT
That is about 12 times the Hiroshima bomb. It released about 367 times the energy of a magnitude 5.0.
Tectonic setting
40 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
30 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 24 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.5Kermadec Islands, New ZealandNovember 16, 1917 · 239 km SW of this epicenter
- 7.0Kermadec Islands, New ZealandJune 13, 1917 · 184 km SW of this epicenter
- 6.9Kermadec Islands, New ZealandJuly 19, 1911 · 262 km SW of this epicenter
- 6.7Kermadec Islands regionMay 4, 1917 · 75 km N of this epicenter
- 6.6Kermadec Islands regionFebruary 13, 1925 · 75 km S of this epicenter
- 6.5Kermadec Islands regionMay 15, 1912 · 283 km W of this epicenter
- 6.4Kermadec Islands regionOctober 19, 1928 · 180 km W of this epicenter
- 6.4Kermadec Islands regionNovember 29, 1928 · 174 km S of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 2 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1917M8.0
Kermadec Islands
1 May 1917 · 133 km away
tsunami
- 1917M7.5
S Of
16 Nov 1917 · 150 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.