Reviewed by USGS40y ago
M5.2 earthquake south of the Kermadec Islands
Tuesday, September 9, 1986, 00:29:15 UTC · 34.914°S, 179.063°E
A magnitude 5.2 earthquake struck south of the Kermadec Islands on Tuesday, September 9, 1986, 00:29:15 UTC, at a depth of 33.0 km (shallow). It is the strongest earthquake within 300 km since an M6.6 on August 23, 1986.
- Magnitude
- 5.2
- Moderate · mb
- Depth
- 33 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
951 tons of TNT
That is about 1/16 of the Hiroshima bomb. It released about 2 times the energy of a magnitude 5.0.
Tectonic setting
37 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
33 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 75 km
USGS has not published any M2.5+ earthquake within 75 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 218 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 6.9south of the Kermadec IslandsSeptember 26, 1985 · 210 km E of this epicenter
- 6.8150 km N of Opotiki, New ZealandDecember 30, 1984 · 240 km SW of this epicenter
- 6.8south of the Kermadec IslandsJanuary 8, 1970 · 27 km W of this epicenter
- 6.6off the east coast of the North Island of New ZealandFebruary 13, 1938 · 119 km S of this epicenter
- 6.6south of the Kermadec IslandsAugust 23, 1986 · 45 km NE of this epicenter
- 6.6south of the Kermadec IslandsSeptember 1, 1937 · 285 km NE of this epicenter
- 6.5south of the Kermadec IslandsNovember 13, 1957 · 288 km NE of this epicenter
- 6.5east of the North Island of New ZealandNovember 7, 1985 · 150 km E of this epicenter