Reviewed by USGS29y ago
M4.8 earthquake south of the Kermadec Islands
Tuesday, August 5, 1997, 01:22:30 UTC · 32.074°S, 178.924°W
A magnitude 4.8 earthquake struck south of the Kermadec Islands on Tuesday, August 5, 1997, 01:22:30 UTC, at a depth of 33.0 km (shallow). It is the strongest earthquake within 300 km since an M4.8 on August 1, 1997.
- Magnitude
- 4.8
- Light · 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
239 tons of TNT
That is about 1/63 of the Hiroshima bomb. A magnitude 5.0 releases about 2 times more energy.
Tectonic setting
85 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 50 km
USGS has not published any M2.5+ earthquake within 50 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1,052 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 · 236 km NE of this epicenter
- 7.5Kermadec Islands, New ZealandNovember 16, 1917 · 268 km NE of this epicenter
- 7.3Kermadec Islands, New ZealandMarch 26, 1963 · 260 km NE of this epicenter
- 7.3Kermadec Islands, New ZealandJuly 25, 1968 · 160 km NE of this epicenter
- 7.2Kermadec Islands, New ZealandFebruary 9, 1978 · 215 km NE of this epicenter
- 7.2Kermadec Islands, New ZealandAugust 2, 1941 · 285 km NE of this epicenter
- 7.2Kermadec Islands, New ZealandApril 17, 1919 · 188 km NE of this epicenter
- 7.1Kermadec Islands, New ZealandJune 29, 1910 · 216 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 4 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 · 150 km away
Limited damage (under $1M)tsunami
- 1976M7.8
Kermadec Islands
14 Jan 1976 · 289 km away · intensity VIII
- 1978M7.7
S Of
9 Feb 1978 · 215 km away
- 1943M7.6
S Of
14 Sep 1943 · 295 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.