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Updated 2014-11-07 01:44:18 UTC

M 4.6 — 245 km ESE of Iwaki, Japan

Magnitude 4.6, depth 18.8 km, 2011-03-23 15:44:02 UTC.

MagnitudeM 4.6
Depth18.8 km
Felt reports—
Statusreviewed
TsunamiNo

Japan → · Iwaki →

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 →
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What to know

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

  • Magnitude M 4.6 at 18.8 km depth.
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#109,443
Magnitude rank in country#9,330
M4.5+ within 250 km, ±15 days1,473
Sequence context1168 events →
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Impact and context

Descriptive indicators available for this event and its surroundings.

8/100Limited context
Felt reports—
Max felt intensity (CDI)—
Instrumental intensity (MMI)—
PAGER alertNot available
Tsunami indicator—
USGS significance326
Depth contextShallow
Nearby major cityTokyo347 km · 14,000,000

Nearby major city

Tokyo347 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 4.6 · 245 km ESE of Iwaki, Japan · 100 kmInteractive 3D view of earthquakes within 100 km of M 4.6 · 245 km ESE of Iwaki, Japan.M 4.6 · 245 km ESE of Iwaki, JapanM 4.5 · 157 km ESE of Iwaki, Japan · 90.3 kmM 5.0 · 223 km E of Namie, Japan · 97.9 kmM 4.6 · 233 km E of Namie, Japan · 94.2 kmM 5.5 · 267 km ESE of Namie, Japan · 75.3 kmM 4.8 · 163 km ESE of Iwaki, Japan · 83.6 kmM 4.7 · 168 km ESE of Iwaki, Japan · 77.3 kmM 4.5 · 265 km ESE of Namie, Japan · 89.8 kmM 4.7 · 224 km ESE of Namie, Japan · 69.9 kmM 4.8 · 211 km ESE of Iwaki, Japan · 44.1 kmM 4.6 · 227 km E of Namie, Japan · 91.4 kmM 4.6 · 186 km ESE of Iwaki, Japan · 60.0 kmM 4.6 · 232 km ESE of Iwaki, Japan · 15.5 kmM 4.5 · 147 km ESE of Iwaki, Japan · 97.6 kmM 4.9 · 224 km ESE of Iwaki, Japan · 34.8 kmM 4.5 · 267 km ESE of Namie, Japan · 81.9 kmM 4.5 · 234 km E of Hasaki, Japan · 27.1 kmM 4.5 · 234 km E of Hasaki, Japan · 28.6 kmM 4.8 · 221 km ESE of Namie, Japan · 73.7 kmM 4.8 · 225 km ESE of Namie, Japan · 74.1 kmM 4.7 · 276 km ESE of Namie, Japan · 77.8 kmM 4.5 · 239 km E of Hasaki, Japan · 23.6 kmM 4.6 · 154 km ENE of Hasaki, Japan · 92.1 kmM 4.8 · 238 km E of Hasaki, Japan · 69.1 kmM 5.7 · 154 km ENE of Hasaki, Japan · 91.7 kmM 4.5 · 172 km ESE of Namie, Japan · 90.7 kmM 4.5 · 215 km E of Iwaki, Japan · 52.2 kmM 4.6 · 239 km E of Hasaki, Japan · 82.2 kmM 4.5 · 251 km E of Namie, Japan · 99.5 kmM 4.5 · 186 km ESE of Iwaki, Japan · 65.9 kmM 4.5 · 275 km E of Iwaki, Japan · 61.6 kmM 4.5 · 157 km ENE of Hasaki, Japan · 92.3 kmM 4.7 · 193 km ESE of Namie, Japan · 90.0 kmM 5.1 · 211 km ESE of Namie, Japan · 74.2 kmM 4.5 · 199 km ENE of Hasaki, Japan · 46.7 kmM 4.9 · 216 km ESE of Namie, Japan · 70.9 kmM 4.6 · 226 km ESE of Namie, Japan · 67.5 kmM 4.8 · 244 km E of Iwaki, Japan · 50.5 kmM 4.7 · 177 km ENE of Hasaki, Japan · 72.4 kmM 4.9 · 169 km ENE of Hasaki, Japan · 77.7 kmM 4.9 · 165 km ENE of Hasaki, Japan · 83.3 kmM 4.6 · 212 km ESE of Iwaki, Japan · 33.2 kmM 4.8 · 168 km ENE of Hasaki, Japan · 77.4 kmM 4.9 · 168 km ENE of Hasaki, Japan · 78.4 kmM 4.6 · 255 km ESE of Namie, Japan · 78.5 kmM 4.5 · 268 km E of Namie, Japan · 97.1 kmM 4.6 · 160 km ENE of Hasaki, Japan · 85.4 kmM 4.6 · 168 km ENE of Hasaki, Japan · 76.8 kmM 4.7 · 246 km ESE of Namie, Japan · 57.4 kmM 4.8 · 294 km ESE of Iwaki, Japan · 58.0 kmM 4.8 · 198 km ESE of Iwaki, Japan · 49.2 kmM 4.6 · 232 km E of Hasaki, Japan · 32.7 kmM 4.5 · 256 km E of Iwaki, Japan · 45.6 kmM 4.6 · 159 km ENE of Hasaki, Japan · 88.4 kmM 4.5 · 226 km ENE of Hasaki, Japan · 19.7 kmM 4.8 · 203 km E of Iwaki, Japan · 64.1 kmM 4.5 · 216 km ESE of Iwaki, Japan · 37.4 kmM 5.1 · 268 km E of Namie, Japan · 96.1 kmM 4.6 · 201 km ESE of Iwaki, Japan · 51.8 kmM 4.6 · off the east coast of Honshu, Japan · 94.1 kmM 5.6 · 206 km ESE of Namie, Japan · 67.0 kmM 4.6 · 233 km ESE of Namie, Japan · 72.2 kmM 4.7 · 259 km E of Namie, Japan · 93.5 kmM 4.5 · 270 km ESE of Namie, Japan · 86.5 kmM 4.9 · 263 km ESE of Namie, Japan · 82.6 kmM 4.5 · 286 km ESE of Namie, Japan · 95.2 kmM 4.8 · 154 km ESE of Iwaki, Japan · 91.1 kmM 4.9 · 145 km ESE of Iwaki, Japan · 99.9 kmM 4.6 · 153 km ESE of Iwaki, Japan · 92.6 kmM 5.0 · 208 km ESE of Iwaki, Japan · 49.1 kmM 4.5 · 270 km ESE of Iwaki, Japan · 37.7 kmM 4.8 · 251 km ESE of Iwaki, Japan · 38.7 kmM 4.6 · 207 km ENE of Hasaki, Japan · 38.4 kmM 4.5 · 262 km ESE of Namie, Japan · 79.5 kmM 5.2 · 255 km E of Namie, Japan · 98.5 kmM 4.5 · 247 km ESE of Namie, Japan · 81.5 kmM 5.0 · 234 km ESE of Iwaki, Japan · 11.9 kmM 4.5 · 244 km ESE of Iwaki, Japan · 5.3 kmM 4.6 · 237 km ENE of Hasaki, Japan · 12.6 kmM 4.9 · 235 km ESE of Iwaki, Japan · 9.9 kmM 4.6 · 165 km ENE of Hasaki, Japan · 80.7 kmM 4.6 · 280 km ESE of Namie, Japan · 80.4 kmM 4.8 · 218 km E of Iwaki, Japan · 52.0 kmM 4.5 · 228 km ESE of Iwaki, Japan · 27.7 kmM 4.9 · 213 km ESE of Iwaki, Japan · 43.2 kmM 4.5 · 225 km ENE of Hasaki, Japan · 21.1 kmM 4.8 · 248 km E of Namie, Japan · 91.8 kmM 4.6 · 161 km ESE of Iwaki, Japan · 89.2 kmM 4.7 · 220 km ESE of Iwaki, Japan · 24.4 kmM 4.5 · off the east coast of Honshu, Japan · 67.5 kmM 5.0 · 172 km ESE of Iwaki, Japan · 73.0 kmM 4.7 · 216 km ESE of Namie, Japan · 63.3 kmM 4.8 · 206 km ESE of Iwaki, Japan · 47.1 kmM 4.6 · 241 km E of Hasaki, Japan · 70.1 kmM 4.8 · 218 km ESE of Iwaki, Japan · 26.7 kmM 4.5 · 295 km ESE of Iwaki, Japan · 59.3 kmM 4.8 · 286 km ESE of Iwaki, Japan · 51.7 kmM 4.7 · 150 km ENE of Hasaki, Japan · 95.5 kmM 4.7 · 211 km ESE of Iwaki, Japan · 42.0 kmM 4.5 · 157 km ESE of Iwaki, Japan · 87.8 kmM 5.2 · 196 km ENE of Hasaki, Japan · 51.4 km
M 4.6 · 245 km ESE of Iwaki, 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 4.5157 km ESE of Iwaki, Japan90.3 km · 2011-04-20 07:40:33 UTCM 5.0223 km E of Namie, Japan97.9 km · 2011-04-19 04:04:30 UTCM 4.6233 km E of Namie, Japan94.2 km · 2011-04-18 03:53:40 UTCM 5.5267 km ESE of Namie, Japan75.3 km · 2011-04-16 20:36:46 UTCM 4.8163 km ESE of Iwaki, Japan83.6 km · 2011-04-15 00:56:27 UTCM 4.7168 km ESE of Iwaki, Japan77.3 km · 2011-04-13 22:05:07 UTCM 4.5265 km ESE of Namie, Japan89.8 km · 2011-04-11 17:35:14 UTCM 4.7224 km ESE of Namie, Japan69.9 km · 2011-04-10 05:23:28 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 4.6 → M 4.6
Depth change+0.0 km
Last update6272136 min
2014-11-07 01:44:18 UTC2014-11-07 01:44:18 UTC

Explore related context

Related or nearby earthquakes

M 4.5 · 256 km ESE of Tomioka, Japan71 km · 2026-05-12 05:33:00 UTCM 4.5 · 109 km E of Tomioka, Japan147 km · 2026-09-14 07:33:04 UTCM 4.5 · 295 km ESE of Onagawa Chō, Japan148 km · 2026-05-10 03:03:39 UTCM 4.4 · 90 km ESE of Tomioka, Japan156 km · 2026-08-23 00:32:24 UTC

Geographic context

CountryJapan →Nearby cityIwaki →Seismic sequenceM 4.6 →

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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.

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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