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Updated 2026-08-15 23:03:39 UTC

M 9.1 — 2011 Great Tohoku Earthquake, Japan

Magnitude 9.1, depth 29.0 km, 2011-03-11 05:46:24 UTC.

MagnitudeM 9.1
Depth29.0 km
Felt reports1459
Statusreviewed
TsunamiNo

Japan →

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 Index51/100Normal
Current 30 days42
Historical monthly median41.5
Historical percentileP51
M5+ in 30 days9
M6+ in 30 days1
Activity trendaround the historical range (+1%)
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 9.1 at 29.0 km depth.
  • 1,459 felt report(s) are associated with the USGS record.
Counts describe detected earthquakes and are not a forecast or hazard assessment.
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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#1
Magnitude rank in country#1
M4.5+ within 250 km, ±15 days1,551
Sequence context1734 events →
Remarkable

Why this event stands out

high magnitude · many felt reports · high USGS significance

99/100
Quake Pulse

Impact and context

Descriptive indicators available for this event and its surroundings.

79/100Very high context
Felt reports1,459
Max felt intensity (CDI)9.1
Instrumental intensity (MMI)8.2
PAGER alertNot available
Tsunami indicator—
USGS significance2,184
Depth contextShallow
Nearby major cityTokyo376 km · 14,000,000

Nearby major city

Tokyo376 km · 14,000,000

Displayed population is the indexed city population, not an estimate of people exposed.

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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.

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Around this epicenter

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

50 km100 km250 km
M 9.1 · 2011 Great Tohoku Earthquake, Japan · 100 kmInteractive 3D view of earthquakes within 100 km of M 9.1 · 2011 Great Tohoku Earthquake, Japan.M 9.1 · 2011 Great Tohoku Earthquake, JapanM 4.7 · 139 km SE of ?funato, Japan · 48.4 kmM 5.3 · 38 km ESE of Ishinomaki, Japan · 58.7 kmM 4.6 · 78 km ESE of Kamaishi, Japan · 73.2 kmM 4.6 · 49 km ENE of Ishinomaki, Japan · 60.8 kmM 4.5 · 100 km SE of Ishinomaki, Japan · 44.5 kmM 4.5 · 55 km ESE of Ishinomaki, Japan · 40.1 kmM 4.6 · 86 km ESE of Ishinomaki, Japan · 13.8 kmM 4.5 · 52 km ESE of Ishinomaki, Japan · 47.5 kmM 4.7 · 101 km ESE of Ishinomaki, Japan · 25.2 kmM 4.6 · 50 km SE of Ishinomaki, Japan · 59.0 kmM 4.7 · 53 km ESE of Ishinomaki, Japan · 49.2 kmM 7.1 · 29 km ESE of Ishinomaki, Japan · 68.6 kmM 4.6 · 48 km ESE of Kamaishi, Japan · 87.5 kmM 4.5 · 78 km ENE of Namie, Japan · 83.9 kmM 4.6 · 110 km ESE of Ishinomaki, Japan · 34.4 kmM 4.8 · 76 km E of Ishinomaki, Japan · 18.5 kmM 4.6 · 76 km E of Ishinomaki, Japan · 18.9 kmM 5.0 · 70 km E of Ishinomaki, Japan · 24.9 kmM 4.6 · 77 km E of Ishinomaki, Japan · 19.0 kmM 4.7 · 62 km ESE of ?funato, Japan · 66.4 kmM 4.7 · 53 km ESE of Ishinomaki, Japan · 44.0 kmM 5.0 · 121 km ESE of Ishinomaki, Japan · 52.9 kmM 5.1 · 117 km SE of Ishinomaki, Japan · 53.4 kmM 4.7 · 76 km E of Ishinomaki, Japan · 18.3 kmM 5.0 · 101 km SE of Ishinomaki, Japan · 57.7 kmM 4.9 · 91 km SE of Ishinomaki, Japan · 52.3 kmM 4.7 · 68 km E of Ishinomaki, Japan · 26.3 kmM 4.5 · 60 km ENE of Namie, Japan · 94.8 kmM 4.8 · 188 km ESE of Ishinomaki, Japan · 95.7 kmM 4.7 · 37 km ESE of Kamaishi, Japan · 92.5 kmM 5.2 · 40 km SSE of ?funato, Japan · 63.2 kmM 4.8 · 24 km SSE of ?funato, Japan · 78.8 kmM 4.5 · 85 km E of Ishinomaki, Japan · 9.3 kmM 4.6 · 92 km E of Ishinomaki, Japan · 11.5 kmM 4.5 · 78 km E of Ishinomaki, Japan · 19.8 kmM 4.6 · 83 km E of Ishinomaki, Japan · 16.1 kmM 4.5 · 56 km ESE of Ishinomaki, Japan · 42.5 kmM 5.1 · 114 km ENE of Namie, Japan · 67.1 kmM 4.6 · 102 km ESE of Ishinomaki, Japan · 24.3 kmM 4.6 · 97 km SE of ?funato, Japan · 29.3 kmM 4.5 · 87 km E of Ishinomaki, Japan · 7.5 kmM 4.5 · 72 km E of Ishinomaki, Japan · 27.7 kmM 6.0 · 18 km SSE of ?funato, Japan · 84.4 kmM 4.6 · 65 km ESE of Ishinomaki, Japan · 34.1 kmM 4.6 · 77 km ENE of Namie, Japan · 80.8 kmM 4.7 · 62 km ESE of Kamaishi, Japan · 77.6 kmM 4.5 · 98 km ENE of Namie, Japan · 72.6 kmM 5.2 · 49 km SSE of ?funato, Japan · 54.0 kmM 4.6 · 81 km E of Ishinomaki, Japan · 13.1 kmM 4.9 · 138 km SE of Ishinomaki, Japan · 69.1 kmM 4.6 · 138 km SE of Ishinomaki, Japan · 67.0 kmM 4.7 · 107 km ESE of Ishinomaki, Japan · 33.6 kmM 4.5 · 134 km SE of ?funato, Japan · 43.6 kmM 4.6 · 116 km SE of ?funato, Japan · 29.0 kmM 6.1 · 114 km E of Namie, Japan · 99.9 kmM 4.7 · 121 km ESE of Kamaishi, Japan · 76.0 kmM 4.5 · 85 km SE of Ishinomaki, Japan · 44.7 kmM 5.2 · 103 km ESE of Kamaishi, Japan · 72.2 kmM 4.5 · 68 km ESE of ?funato, Japan · 55.8 kmM 4.7 · 56 km ENE of Ishinomaki, Japan · 50.5 kmM 4.9 · 78 km E of Ishinomaki, Japan · 16.5 kmM 6.2 · 62 km E of Ishinomaki, Japan · 34.2 kmM 4.8 · 69 km ENE of Namie, Japan · 87.7 kmM 5.3 · 55 km SE of Kamaishi, Japan · 72.6 kmM 4.7 · 118 km E of Namie, Japan · 71.2 kmM 4.7 · 126 km E of Namie, Japan · 67.9 kmM 4.7 · 146 km E of Namie, Japan · 93.7 kmM 4.7 · 64 km E of Namie, Japan · 99.5 kmM 5.3 · 42 km ENE of Ishinomaki, Japan · 63.6 kmM 4.6 · 159 km ESE of Ishinomaki, Japan · 81.1 kmM 4.5 · 171 km ESE of Ishinomaki, Japan · 87.8 kmM 4.5 · 74 km E of Ishinomaki, Japan · 26.3 kmM 6.2 · 36 km SSE of ?funato, Japan · 68.0 kmM 4.8 · 153 km ESE of Kamaishi, Japan · 91.8 kmM 4.8 · 164 km ESE of Ishinomaki, Japan · 73.8 kmM 4.9 · 49 km SE of ?funato, Japan · 55.3 kmM 4.7 · 152 km E of Namie, Japan · 83.4 kmM 4.7 · 94 km E of Ishinomaki, Japan · 11.0 kmM 4.8 · 143 km ESE of Kamaishi, Japan · 91.4 kmM 5.8 · 28 km SE of Kamaishi, Japan · 90.5 kmM 4.8 · 62 km SE of ?funato, Japan · 50.3 kmM 5.1 · near the east coast of Honshu, Japan · 51.5 kmM 4.6 · 87 km E of Ishinomaki, Japan · 6.9 kmM 4.6 · 87 km E of Ishinomaki, Japan · 7.8 kmM 4.5 · 178 km ESE of ?funato, Japan · 99.7 kmM 4.7 · 72 km ENE of Namie, Japan · 84.2 kmM 4.8 · 84 km E of Namie, Japan · 90.0 kmM 5.0 · 157 km ESE of Ishinomaki, Japan · 81.2 kmM 4.5 · 152 km SE of Ishinomaki, Japan · 79.3 kmM 4.6 · 125 km ESE of Ishinomaki, Japan · 39.4 kmM 4.5 · 139 km ESE of Ishinomaki, Japan · 49.3 kmM 4.5 · 56 km ENE of Namie, Japan · 98.0 kmM 4.9 · 44 km ESE of Ishinomaki, Japan · 50.2 kmM 4.5 · 118 km ESE of Ishinomaki, Japan · 29.4 kmM 4.8 · 78 km ESE of Kamaishi, Japan · 84.4 kmM 4.7 · 130 km ESE of ?funato, Japan · 68.6 kmM 4.6 · 119 km SE of Ishinomaki, Japan · 59.6 kmM 4.9 · 116 km ENE of Namie, Japan · 65.2 kmM 4.8 · 121 km E of Namie, Japan · 97.4 kmM 4.6 · 129 km ESE of Ishinomaki, Japan · 47.7 km
M 9.1 · 2011 Great Tohoku Earthquake, Japan100 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.

Open sequence →

Nearby events · 100 km

M 4.7139 km SE of ?funato, Japan48.4 km · 2011-04-09 16:57:27 UTCM 5.338 km ESE of Ishinomaki, Japan58.7 km · 2011-04-09 09:42:21 UTCM 4.678 km ESE of Kamaishi, Japan73.2 km · 2011-04-09 06:29:42 UTCM 4.649 km ENE of Ishinomaki, Japan60.8 km · 2011-04-09 02:59:34 UTCM 4.5100 km SE of Ishinomaki, Japan44.5 km · 2011-04-08 13:20:28 UTCM 4.555 km ESE of Ishinomaki, Japan40.1 km · 2011-04-08 02:21:06 UTCM 4.686 km ESE of Ishinomaki, Japan13.8 km · 2011-04-07 15:31:27 UTCM 4.552 km ESE of Ishinomaki, Japan47.5 km · 2011-04-07 15:25:14 UTC
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USGS data evolution

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

Revisions1
Magnitude change+0.0M 9.1 → M 9.1
Depth change+0.0 km
Last update79232 min
2026-08-15 23:03:39 UTC2026-08-15 23:03:39 UTC

Explore related context

Related or nearby earthquakes

M 4.6 · 68 km ESE of Onagawa Chō, Japan14 km · 2026-08-04 14:00:26 UTCM 4.6 · 27 km E of Onagawa Chō, Japan55 km · 2026-04-04 10:36:47 UTCM 4.8 · 65 km ESE of Ōfunato, Japan55 km · 2026-03-06 20:31:51 UTCM 4.5 · 27 km SE of Onagawa Chō, Japan60 km · 2026-04-12 13:00:45 UTC

Geographic context

CountryJapan →Seismic sequenceM 9.1 →

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Putting this earthquake in context

An earthquake record can change after the first automatic publication as additional stations contribute data and analysts refine the solution.

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.

Important limits

If the earthquake creates a safety concern, follow local authorities and official warning channels rather than relying on a public data website.

Read the methodology →

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