Updated 2025-12-22 18:58:46 UTC

M 8.1 — 2021 Kermadec Islands, New Zealand Earthquake

Magnitude 8.1, depth 28.9 km, 2021-03-04 19:28:33 UTC.

MagnitudeM 8.1
Depth28.9 km
Felt reports13
Statusreviewed
TsunamiYes
Quake Pulse Activity Index

Activity trend

A high index means recent activity is high relative to the selected historical baseline. It does not mean that a larger earthquake is about to occur.

Quake Pulse Activity Index56/100Normal
Current 30 days11
Historical monthly median10.5
Historical percentileP56
M5+ in 30 days4
M6+ in 30 days0
Activity trendaround the historical range (+5%)
Baseline months: 60Last calculation: 2026-09-03 06:17:39How the index works →
Quake Pulse

What to know

A short factual reading of this event from the available observations.

  • Magnitude M 8.1 at 28.9 km depth.
  • 13 felt report(s) are associated with the USGS record.
  • The USGS tsunami flag is enabled for this event.
  • The available PAGER level is GREEN.
Counts describe detected earthquakes and are not a forecast or hazard assessment.
Quake Pulse

Within the Quake Pulse database

Long-term comparisons are more robust at higher magnitudes because small-earthquake detection capability has changed over time.

Magnitude rank in database#18
Magnitude rank in country#1
M4.5+ within 250 km, ±15 days481
Sequence context487 events →
Remarkable

Why this event stands out

high magnitude · tsunami flag · high USGS significance

87/100
Quake Pulse

Impact and context

Descriptive indicators available for this event and its surroundings.

74/100High context
Felt reports13
Max felt intensity (CDI)9.1
Instrumental intensity (MMI)8.0
PAGER alertGREEN
Tsunami indicatorYES
USGS significance1,021
Depth contextShallow
Nearby major city—
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These indicators describe data available after detection. They are neither a forecast nor a direct estimate of damage or individual risk.

Quake Pulse

Around this epicenter

Nearby events observed around this epicenter. Spatial proximity does not necessarily mean they belong to the same sequence.

M 8.1 · 2021 Kermadec Islands, New Zealand Earthquake · 100 kmInteractive 3D view of earthquakes within 100 km of M 8.1 · 2021 Kermadec Islands, New Zealand Earthquake.M 8.1 · 2021 Kermadec Islands, New Zealand EarthquakeM 4.5 · Kermadec Islands region · 39.0 kmM 4.8 · Kermadec Islands region · 30.3 kmM 4.5 · Kermadec Islands region · 65.2 kmM 5.6 · Kermadec Islands, New Zealand · 38.0 kmM 4.6 · Kermadec Islands, New Zealand · 33.2 kmM 4.5 · Kermadec Islands region · 82.1 kmM 4.8 · Kermadec Islands region · 43.4 kmM 6.4 · Kermadec Islands, New Zealand · 46.5 kmM 4.5 · Kermadec Islands region · 55.3 kmM 4.5 · Kermadec Islands, New Zealand · 54.2 kmM 4.5 · Kermadec Islands region · 61.5 kmM 4.7 · Kermadec Islands region · 72.9 kmM 4.6 · Kermadec Islands, New Zealand · 35.2 kmM 4.5 · Kermadec Islands region · 78.2 kmM 4.5 · Kermadec Islands, New Zealand · 11.9 kmM 4.9 · Kermadec Islands, New Zealand · 56.4 kmM 4.6 · Kermadec Islands, New Zealand · 26.8 kmM 4.6 · Kermadec Islands, New Zealand · 49.1 kmM 4.5 · Kermadec Islands, New Zealand · 10.7 kmM 5.0 · Kermadec Islands, New Zealand · 65.5 kmM 4.9 · Kermadec Islands region · 75.9 kmM 4.8 · Kermadec Islands, New Zealand · 26.5 kmM 4.9 · Kermadec Islands, New Zealand · 14.7 kmM 4.8 · Kermadec Islands region · 88.8 kmM 4.5 · Kermadec Islands region · 57.5 kmM 4.6 · Kermadec Islands region · 79.0 kmM 5.0 · Kermadec Islands region · 36.1 kmM 5.1 · Kermadec Islands region · 57.5 kmM 5.2 · Kermadec Islands region · 63.8 kmM 4.5 · Kermadec Islands region · 70.2 kmM 5.3 · Kermadec Islands region · 71.2 kmM 4.6 · Kermadec Islands region · 94.5 kmM 4.9 · Kermadec Islands region · 88.0 kmM 4.6 · Kermadec Islands, New Zealand · 55.6 kmM 4.7 · Kermadec Islands region · 48.9 kmM 4.9 · Kermadec Islands, New Zealand · 74.9 kmM 4.8 · Kermadec Islands, New Zealand · 9.6 kmM 4.8 · Kermadec Islands region · 77.9 kmM 4.6 · Kermadec Islands, New Zealand · 21.7 kmM 4.7 · Kermadec Islands, New Zealand · 16.0 kmM 5.0 · Kermadec Islands, New Zealand · 12.4 kmM 4.5 · Kermadec Islands, New Zealand · 41.2 kmM 4.5 · Kermadec Islands, New Zealand · 42.2 kmM 4.7 · Kermadec Islands region · 87.2 kmM 4.9 · Kermadec Islands region · 86.6 kmM 5.9 · Kermadec Islands, New Zealand · 57.5 kmM 4.7 · Kermadec Islands region · 56.9 kmM 4.8 · Kermadec Islands region · 49.8 kmM 4.5 · Kermadec Islands, New Zealand · 95.1 kmM 4.8 · Kermadec Islands, New Zealand · 43.6 kmM 4.9 · Kermadec Islands, New Zealand · 59.4 kmM 4.9 · Kermadec Islands region · 45.0 kmM 4.6 · Kermadec Islands, New Zealand · 17.9 kmM 4.8 · Kermadec Islands, New Zealand · 23.8 kmM 4.5 · Kermadec Islands region · 71.9 kmM 4.5 · Kermadec Islands, New Zealand · 98.3 kmM 4.6 · Kermadec Islands, New Zealand · 28.6 kmM 4.8 · Kermadec Islands, New Zealand · 55.3 kmM 4.5 · Kermadec Islands region · 82.4 kmM 5.1 · Kermadec Islands region · 43.1 kmM 4.6 · Kermadec Islands region · 66.5 kmM 4.8 · Kermadec Islands region · 66.6 kmM 4.5 · Kermadec Islands, New Zealand · 39.7 kmM 4.6 · Kermadec Islands, New Zealand · 11.0 kmM 4.9 · Kermadec Islands region · 56.0 kmM 4.5 · Kermadec Islands region · 98.2 kmM 4.5 · Kermadec Islands, New Zealand · 28.6 kmM 4.8 · Kermadec Islands region · 93.1 kmM 4.9 · Kermadec Islands, New Zealand · 28.7 kmM 4.5 · Kermadec Islands region · 66.2 kmM 4.8 · Kermadec Islands region · 59.8 kmM 4.8 · Kermadec Islands region · 97.2 kmM 4.5 · Kermadec Islands, New Zealand · 11.5 kmM 4.6 · Kermadec Islands region · 83.2 kmM 4.5 · Kermadec Islands region · 45.3 kmM 4.8 · Kermadec Islands, New Zealand · 24.1 kmM 4.9 · Kermadec Islands, New Zealand · 13.4 kmM 4.6 · Kermadec Islands, New Zealand · 43.2 kmM 4.5 · Kermadec Islands, New Zealand · 16.5 kmM 5.1 · Kermadec Islands region · 27.2 kmM 5.2 · Kermadec Islands region · 66.5 kmM 5.1 · Kermadec Islands, New Zealand · 26.7 kmM 5.0 · Kermadec Islands, New Zealand · 40.8 kmM 4.8 · Kermadec Islands, New Zealand · 4.2 kmM 5.0 · Kermadec Islands, New Zealand · 7.6 kmM 4.7 · Kermadec Islands region · 48.5 kmM 4.9 · Kermadec Islands region · 90.3 kmM 4.6 · Kermadec Islands region · 34.1 kmM 4.9 · Kermadec Islands region · 56.9 kmM 5.2 · Kermadec Islands region · 45.8 kmM 4.6 · Kermadec Islands region · 55.3 kmM 5.0 · Kermadec Islands, New Zealand · 28.4 kmM 5.1 · Kermadec Islands region · 93.0 kmM 4.5 · Kermadec Islands region · 39.0 kmM 4.6 · Kermadec Islands region · 39.8 kmM 4.9 · Kermadec Islands, New Zealand · 71.8 kmM 5.0 · Kermadec Islands region · 94.3 kmM 4.6 · Kermadec Islands region · 84.0 kmM 4.9 · Kermadec Islands, New Zealand · 26.1 kmM 4.6 · Kermadec Islands region · 30.0 km
M 8.1 · 2021 Kermadec Islands, New Zealand Earthquake100 km100 Recent earthquakes

Descriptive map centered on the epicenter; it does not represent felt intensity or risk.

Sequence context

This event belongs to a sequence detected by Quake Pulse.

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Nearby events · 100 km

Quake Pulse

USGS data evolution

Earthquake parameters can be revised after first publication. This timeline shows versions retained by Quake Pulse.

Revisions1
Magnitude change+0.0M 8.1 → M 8.1
Depth change+0.0 km
Last update419315 min
2025-12-22 18:58:46 UTC2025-12-22 18:58:46 UTC

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Putting this earthquake in context

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Interpret the numbers

Magnitude, depth, felt reports and status describe different parts of the event. None of them alone predicts the consequences for a specific city.

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