Reviewed by USGS5y ago
M4.6 earthquake south of the Kermadec Islands
Tuesday, April 27, 2021, 02:38:32 UTC · 32.618°S, 178.876°W
A magnitude 4.6 earthquake struck south of the Kermadec Islands on Tuesday, April 27, 2021, 02:38:32 UTC, at a depth of 35.0 km (shallow). It is the strongest earthquake within 300 km since an M4.7 on April 27, 2021.
- Magnitude
- 4.6
- Light · mb
- Depth
- 35 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
120 tons of TNT
That is about 1/126 of the Hiroshima bomb. A magnitude 5.0 releases about 4 times more energy.
Tectonic setting
111 km
from the nearest mapped plate boundary, between the Kermadec and Australian plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
35 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 1,797 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 · 263 km NE of this epicenter
- 7.4south of the Kermadec IslandsJune 18, 2020 · 121 km SE of this epicenter
- 7.4Kermadec Islands regionMay 16, 2006 · 99 km NW of this epicenter
- 7.3Kermadec Islands, New ZealandJuly 25, 1968 · 214 km N of this epicenter
- 7.3Kermadec Islands, New ZealandJune 15, 2019 · 232 km N of this epicenter
- 7.2Kermadec Islands, New ZealandFebruary 9, 1978 · 259 km NE of this epicenter
- 7.2Kermadec Islands, New ZealandApril 17, 1919 · 242 km N of this epicenter
- 7.1Kermadec Islands, New ZealandJune 29, 1910 · 254 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 5 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 · 207 km away
Limited damage (under $1M)tsunami
- 1978M7.7
S Of
9 Feb 1978 · 259 km away
- 2020M7.4
S Of, Raoul
18 Jun 2020 · 121 km away · intensity VII
tsunami
- 2019M7.2
S Of, Raoul
15 Jun 2019 · 215 km away
tsunami
- 2013M6.5
S Of, Raoul
30 Sep 2013 · 195 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.