Reviewed by USGSNew Zealand106y ago
M6.7 earthquake 5 km SSW of Hastings, New Zealand
Tuesday, June 28, 1921, 13:58:43 UTC · 39.685°S, 176.831°E
A magnitude 6.7 earthquake struck 5 km SSW of Hastings, New Zealand on Tuesday, June 28, 1921, 13:58:43 UTC, at a depth of 25.0 km (shallow). It is the strongest earthquake within 300 km since an M6.8 on August 5, 1917.
- Magnitude
- 6.7
- Strong · mw
- Depth
- 25 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- VI
- Strong (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
169 kilotons of TNT
That is about 11 times the Hiroshima bomb. It released about 355 times the energy of a magnitude 5.0.
Tectonic setting
76 km
from the nearest mapped plate boundary, between the Kermadec and Australian plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
25 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 6 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.044 km N of Whakatane, New ZealandNovember 22, 1914 · 236 km N of this epicenter
- 6.9144 km SE of Waipawa, New ZealandAugust 8, 1904 · 278 km S of this epicenter
- 6.856 km SSE of Castlepoint, New ZealandAugust 5, 1917 · 191 km S of this epicenter
- 6.748 km ENE of Opotiki, New ZealandOctober 6, 1914 · 214 km NE of this epicenter
- 6.384 km SSE of Castlepoint, New ZealandSeptember 12, 1919 · 212 km S of this epicenter
- 5.8188 km ESE of Castlepoint, New ZealandAugust 6, 1917 · 254 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 10 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 1 recorded deaths. The most severe:
- 1914
North Island
6 Oct 1914 · 241 km away · intensity VIII
1 deathModerate damage ($1–5M)tsunami
- 1855M8.0
Wellington,Waiouru,Wanganui,Otaki
23 Jan 1855 · 233 km away
Severe damage ($5–24M)tsunami
- 1848M7.9
N.
15 Oct 1848 · 267 km away
Limited damage (under $1M)tsunami
- 1843M7.5
Wanganui
8 Jul 1843 · 158 km away
tsunami
- 1904M7.5
E Of North Island
8 Aug 1904 · 92 km away
tsunami
- 1880M7.0
Gisborne
8 Sep 1880 · 197 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.