Reviewed by USGS29y ago
M6.9 earthquake in Kermadec Islands region
Saturday, May 3, 1997, 16:46:02 UTC · 31.791°S, 179.382°W
A magnitude 6.9 earthquake struck in Kermadec Islands region on Saturday, May 3, 1997, 16:46:02 UTC, at a depth of 108.3 km (intermediate). It is the strongest earthquake within 300 km since an M7.0 on May 14, 1989.
- Magnitude
- 6.9
- Strong · mwc
- Depth
- 108 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: 100 km aftershock search area
In context
How big was it, and why here?
Energy released
338 kilotons of TNT
That is about 22 times the Hiroshima bomb. It released about 708 times the energy of a magnitude 5.0.
Tectonic setting
33 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
108 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 100 km
USGS lists 12 M2.5+ earthquakes within 100 km in the following 30 days; the largest was M7.1 on May 25, 1997. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 7.1south of the Kermadec Islands29y ago · 86 km SW of this epicenter
- 4.4Kermadec Islands region29y ago · 58 km NE of this epicenter
- 4.5Kermadec Islands region29y ago · 40 km NE of this epicenter
- 4.3south of the Kermadec Islands29y ago · 73 km SW of this epicenter
- 4.6Kermadec Islands region29y ago · 60 km E of this epicenter
- 4.5Kermadec Islands region29y ago · 38 km E of this epicenter
- 4.5Kermadec Islands region29y ago · 9 km W of this epicenter
- 4.4south of the Kermadec Islands29y ago · 85 km SW of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1,023 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 · 267 km E of this epicenter
- 7.5Kermadec Islands, New ZealandNovember 16, 1917 · 261 km NE of this epicenter
- 7.3Kermadec Islands, New ZealandMarch 26, 1963 · 258 km NE of this epicenter
- 7.3Kermadec Islands, New ZealandJuly 25, 1968 · 161 km NE of this epicenter
- 7.2Kermadec Islands, New ZealandFebruary 9, 1978 · 228 km NE of this epicenter
- 7.2Kermadec Islands, New ZealandAugust 2, 1941 · 281 km NE of this epicenter
- 7.2Kermadec Islands, New ZealandApril 17, 1919 · 189 km NE of this epicenter
- 7.1Kermadec Islands, New ZealandJune 29, 1910 · 238 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 3 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1968M7.3
S Of, Raoul
25 Jul 1968 · 144 km away
Limited damage (under $1M)tsunami
- 1976M7.8
Kermadec Islands
14 Jan 1976 · 293 km away · intensity VIII
- 1978M7.7
S Of
9 Feb 1978 · 229 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.