Reviewed by USGSNew Zealand58y ago
M6.2 earthquake 88 km W of Riverton, New Zealand
Wednesday, September 25, 1968, 07:02:50 UTC · 46.405°S, 166.868°E
A magnitude 6.2 earthquake struck 88 km W of Riverton, New Zealand on Wednesday, September 25, 1968, 07:02:50 UTC, at a depth of 10.0 km (shallow). It is the strongest earthquake within 300 km since an M6.7 on January 13, 1954.
- Magnitude
- 6.2
- Strong · mw
- Depth
- 10 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
33 kilotons of TNT
That is about 2 times the Hiroshima bomb. It released about 70 times the energy of a magnitude 5.0.
Tectonic setting
86 km
from the nearest mapped plate boundary, between the Pacific and Australian plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
10 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 15 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.5173 km WSW of Riverton, New ZealandSeptember 1, 1945 · 95 km SW of this epicenter
- 7.015 km WNW of Te Anau, New ZealandDecember 16, 1938 · 126 km NE of this epicenter
- 6.8off the west coast of the South Island of New ZealandJanuary 12, 1954 · 294 km SW of this epicenter
- 6.7off the west coast of the South Island of New ZealandJanuary 13, 1954 · 282 km SW of this epicenter
- 6.762 km WNW of Te Anau, New ZealandAugust 2, 1943 · 130 km N of this epicenter
- 6.6115 km WNW of Te Anau, New ZealandDecember 16, 1938 · 175 km N of this epicenter
- 6.5248 km SW of Bluff, New ZealandFebruary 15, 1922 · 229 km S of this epicenter
- 6.5off the west coast of the South Island of New ZealandJanuary 12, 1954 · 277 km SW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 1 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1826M8.0
Fjordland
1826 · 73 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.