Sequence · 2026-04-19

M 6.1 · Observed seismic cluster · 88 km NNE of Hihifo, Tonga

Explore clusters of M4.5+ events observed around significant earthquakes. These clusters are descriptive and are not presented as earthquake predictions.

M4.5+ events in cluster4
M6+1
Analysis radius196 km
Observation window14 days
Largest secondary eventM 4.7
Quake Pulse · Observed cluster

What the sequence shows

After the M 6.1 reference event, Quake Pulse counts 0 M4+ event(s) in the first 24 hours and 1 in the first 7 days. Fourteen-day M4.5+ activity is about 0.7× the average equivalent derived from the previous year. The largest secondary event is M 1.4 below the reference event.

42/100Sequence score
Events in the previous 24 h1
In the first hour0
In the first 24 hours0
In the first 7 days1
Within 14 days3
Peak one-hour count1

Local historical context

Descriptive comparison with M4.5+ events observed in the same radius during the 365 days before the sequence.

M4.5+ events / 365 d105Average 14-day equivalent4.0Activity / baseline ratio0.7×

A ratio above 1 means denser M4.5+ activity than the average equivalent derived from the previous 365 days. It is not a risk measure or a forecast.

Reference event

Largest secondary eventM 4.7Magnitude gapM 1.4Observed duration9.3 d

Earlier events are shown as context only. They are not labelled precursors and should not be interpreted as predictive signals.

Evolving sequence map

Shows M4+ cluster events according to elapsed time after the reference event.

88 km NNE of Hihifo, Tonga · 196 kmInteractive 3D view of earthquakes within 196 km of 88 km NNE of Hihifo, Tonga.88 km NNE of Hihifo, Tonga
88 km NNE of Hihifo, Tonga196 km0 Recent earthquakes

Detailed timeline

Dots represent M4+ events retained by the sequence detector. Dot size depends on magnitude.

Sequences are descriptive groupings based on spatial and temporal proximity. Quake Pulse does not establish a causal link between every event here and does not provide earthquake forecasts.

Quake Pulse

Main-event impact

14 Felt reports · PAGER GREEN · Shallow

41/100
Impact and context →

M4.5+ events in cluster

MagnitudeLocationDepthTime
M 6.188 km NNE of Hihifo, Tonga36.0 km2026-04-19 17:34:47 UTCView event →
M 4.5104 km N of Hihifo, Tonga23.4 km2026-04-24 05:39:31 UTCView event →
M 4.5106 km E of Hihifo, Tonga10.0 km2026-04-28 05:37:30 UTCView event →
M 4.7116 km NNE of Hihifo, Tonga10.0 km2026-04-29 01:44:15 UTCView event →

Interpretation

Explore clusters of M4.5+ events observed around significant earthquakes. These clusters are descriptive and are not presented as earthquake predictions. Historical small-earthquake detection varies through time. Long-term comparisons are most robust at higher magnitude thresholds.

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