Sequence · 2009-08-09

M 7.1 · Observed seismic cluster · 161 km S of ?yama, Japan

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 cluster6
M6+3
Analysis radius356 km
Observation window14 days
Largest secondary eventM 6.6
Quake Pulse

Sequence timeline

Within first 24 hours2
Within first 7 days6
Observed duration4.7 d
Gap from reference eventM 0.5
0 h4.7 d
Quake Pulse

Main-event impact

433 Felt reports · Intermediate

66/100
Impact and context →

M4.5+ events in cluster

MagnitudeLocationDepthTime
M 7.1161 km S of ?yama, Japan292.0 km2009-08-09 10:55:55 UTCView event →
M 4.8178 km S of ?yama, Japan305.7 km2009-08-09 16:01:26 UTCView event →
M 6.28 km NE of Sagara, Japan40.4 km2009-08-10 20:07:09 UTCView event →
M 6.6244 km SSE of Tateyama, Japan53.0 km2009-08-12 22:48:51 UTCView event →
M 4.7255 km SSE of Tateyama, Japan77.2 km2009-08-13 01:53:10 UTCView event →
M 4.5Izu Islands, Japan region446.1 km2009-08-14 03:57:00 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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