Reviewed by USGSNew Zealand98y ago
M6.3 earthquake 50 km ESE of Castlepoint, New Zealand
Wednesday, February 12, 1930, 06:21:30 UTC · 41.085°S, 176.770°E
A magnitude 6.3 earthquake struck 50 km ESE of Castlepoint, New Zealand on Wednesday, February 12, 1930, 06:21:30 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M6.7 on June 28, 1921.
- Magnitude
- 6.3
- 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 earthquake
In context
How big was it, and why here?
Energy released
40 kilotons of TNT
That is about 3 times the Hiroshima bomb. It released about 83 times the energy of a magnitude 5.0.
Tectonic setting
69 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
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 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 5 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 6.9144 km SE of Waipawa, New ZealandAugust 8, 1904 · 123 km S of this epicenter
- 6.856 km SSE of Castlepoint, New ZealandAugust 5, 1917 · 42 km SW of this epicenter
- 6.75 km SSW of Hastings, New ZealandJune 28, 1921 · 156 km N of this epicenter
- 6.384 km SSE of Castlepoint, New ZealandSeptember 12, 1919 · 57 km S of this epicenter
- 5.8188 km ESE of Castlepoint, New ZealandAugust 6, 1917 · 138 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 9 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 3 recorded deaths. The most severe:
- 1848M6.0
Awatere River, Marlborough
18 Oct 1848 · 240 km away
3 deathstsunami
- 1855M8.0
Wellington,Waiouru,Wanganui,Otaki
23 Jan 1855 · 149 km away
Severe damage ($5–24M)tsunami
- 1848M7.9
N.
15 Oct 1848 · 191 km away
Limited damage (under $1M)tsunami
- 1843M7.5
Wanganui
8 Jul 1843 · 199 km away
tsunami
- 1904M7.5
E Of North Island
8 Aug 1904 · 68 km away
tsunami
- 1895M6.0
Taupo
18 Aug 1895 · 262 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.