Reviewed by USGS44y ago
M7.0 earthquake in Kermadec Islands region
Wednesday, January 26, 1983, 16:02:21 UTC · 30.383°S, 179.339°W
A magnitude 7.0 earthquake struck in Kermadec Islands region on Wednesday, January 26, 1983, 16:02:21 UTC, at a depth of 238.0 km (intermediate). It is the strongest earthquake within 300 km since an M7.1 on December 26, 1981.
- Magnitude
- 7.0
- Major · mw
- Depth
- 238 km
- Intermediate
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 200 km aftershock search area
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
10 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: intermediate
238 km
Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.
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 lists 3 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M6.0 on February 7, 1983. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 595 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.21917 Kermadec Islands, New Zealand EarthquakeMay 1, 1917 · 272 km E of this epicenter
- 8.01976 Kermadec Islands, New Zealand EarthquakeJanuary 14, 1976 · 272 km NE of this epicenter
- 7.5Kermadec Islands, New ZealandNovember 16, 1917 · 156 km E of this epicenter
- 7.3Kermadec Islands regionSeptember 14, 1959 · 268 km NE of this epicenter
- 7.3Kermadec Islands, New ZealandMarch 26, 1963 · 166 km E of this epicenter
- 7.3Kermadec Islands, New ZealandJuly 25, 1968 · 123 km E of this epicenter
- 7.2Kermadec Islands, New ZealandFebruary 9, 1978 · 193 km E of this epicenter
- 7.2Kermadec Islands, New ZealandAugust 2, 1941 · 180 km E of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 7 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1976M7.9
Kermadec Islands
14 Jan 1976 · 226 km away
Limited damage (under $1M)tsunami
- 1968M7.3
S Of, Raoul
25 Jul 1968 · 101 km away
Limited damage (under $1M)tsunami
- 1917M8.0
Kermadec Islands
1 May 1917 · 261 km away
tsunami
- 1976M7.8
Kermadec Islands
14 Jan 1976 · 210 km away · intensity VIII
- 1978M7.7
S Of
9 Feb 1978 · 192 km away
- 1943M7.6
S Of
14 Sep 1943 · 229 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.