Reviewed by USGSNew Zealand98y ago
M7.0 earthquake 30 km NW of Amberley, New Zealand
Saturday, March 9, 1929, 10:50:33 UTC · 42.986°S, 172.438°E
A magnitude 7.0 earthquake struck 30 km NW of Amberley, New Zealand on Saturday, March 9, 1929, 10:50:33 UTC, at a depth of 20.0 km (shallow). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.
- Magnitude
- 7.0
- Major · mw
- Depth
- 20 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- VII
- Very 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
477 kilotons of TNT
That is about 32 times the Hiroshima bomb. It released about 1,000 times the energy of a magnitude 5.0.
Tectonic setting
51 km
from the nearest mapped plate boundary, between the Australian and Pacific plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
20 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 200 km
USGS has not published any M2.5+ earthquake within 200 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1 M5.0+ earthquake within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 6 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 20 recorded deaths. The most severe:
- 1929M7.5
South Island
16 Jun 1929 · 138 km away
17 deathsModerate damage ($1–5M)tsunami
- 1848M6.0
Awatere River, Marlborough
18 Oct 1848 · 195 km away
3 deathstsunami
- 1855M8.0
Wellington,Waiouru,Wanganui,Otaki
23 Jan 1855 · 286 km away
Severe damage ($5–24M)tsunami
- 1848M7.9
N.
15 Oct 1848 · 253 km away
Limited damage (under $1M)tsunami
- 1913M6.8
Tasman Sea
22 Feb 1913 · 153 km away · intensity VIII
Limited damage (under $1M)tsunami
- 1922M6.3
Se. New Zealand
25 Dec 1922 · 46 km away · intensity VII
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.