Catalogue time, not a wave simulation
The replay reveals reports at their recorded JST origin times. Station dots show observed Shindo, but the moment they appear is not a measured seismic-wave arrival time.
DAILY EARTHQUAKE ARCHIVE
Earthquakes in Japan on April 21, 2021
Replay earthquakes recorded on this day at their actual occurrence times and inspect every available report.
- earthquakes
- 19
- strongest Shindo
- 4
- largest magnitude
- M4.5
- Shindo 1+ events
- 19
Replay one day of earthquakes
2021-04-21 · JST00:00:00Pause
Shindo12345−5+6−6+7
00:0006:0012:0018:0024:00
JISHINDESU catalogue organised from JMA and P2PQuake data. Times use JST. Points are reported epicentres and observations, not simulated wave propagation.
How to read the record for April 21, 2021
The JISHINDESU catalogue contains 19 earthquakes for this day; 19 reached maximum Shindo 1 or higher. The day's highest Shindo was 4, and its largest reported magnitude was M4.5.
Earthquake with the day's highest ShindoAdjacent Sea of Tokara Islands07:45:00 JST · M3.8 · Shindo 4→01 02 03
Shindo and magnitude measure different things
Magnitude describes the earthquake at its source; Shindo describes shaking at each station. One earthquake can therefore produce different Shindo readings by location.
Shindo and magnitude explained →A record can be updated later
Follow-up bulletins and corrections for the same earthquake are consolidated into one record. Each report page shows the current values and any available revision history.
Data and methodology →JISHINDESU ON YOUR PHONE
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This page preserves one past day. In the app, save your home, family or destination and check locally observed Shindo when a new earthquake is reported.
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Earthquake reports
19 earthquakes · Shindo 4 · M4.5
April 21, 2021
- 震度2Central Nagano Prefecture長野県中部02:40 JSTconfirmedM4.5Depth: 170 km
- 震度2Southern Kyoto Prefecture京都府南部04:43 JSTconfirmedM3.3Depth: 10 km
- 震度1Adjacent Sea of Tokara Islandsトカラ列島近海06:05 JSTconfirmedM2.6Depth: 20 km
- 震度4Adjacent Sea of Tokara Islandsトカラ列島近海07:45 JSTconfirmedM3.8Depth: 20 km
- 震度1Adjacent Sea of Tokara Islandsトカラ列島近海08:50 JSTconfirmedM2.8Depth: 10 km
- 震度1Adjacent Sea of Tokara Islandsトカラ列島近海09:31 JSTconfirmedM2.8Depth: 20 km
- 震度1Adjacent Sea of Tokara Islandsトカラ列島近海10:13 JSTconfirmedM2.5Depth: 10 km
- 震度1Adjacent Sea of Tokara Islandsトカラ列島近海12:11 JSTconfirmedM2.4Depth: 20 km
- 震度1Off the Coast of Fukushima Prefecture福島県沖15:05 JSTconfirmedM4.1Depth: 50 km
- 震度1Off the Coast of Fukushima Prefecture福島県沖16:28 JSTconfirmedM3.8Depth: 50 km
- 震度3Adjacent Sea of Izu-Oshima Island伊豆大島近海20:46 JSTconfirmedM3.0Depth: 0 km
- 震度2Adjacent Sea of Izu-Oshima Island伊豆大島近海20:55 JSTconfirmedM3.1Depth: 0 km
- 震度1Adjacent Sea of Izu-Oshima Island伊豆大島近海21:02 JSTconfirmedM2.4Depth: 10 km
- 震度3Adjacent Sea of Izu-Oshima Island伊豆大島近海21:29 JSTconfirmedM4.3Depth: 10 km
- 震度2Adjacent Sea of Izu-Oshima Island伊豆大島近海22:07 JSTconfirmedM3.2Depth: 10 km
- 震度1Adjacent Sea of Izu-Oshima Island伊豆大島近海22:30 JSTconfirmedM2.6Depth: 0 km
- 震度1Adjacent Sea of Izu-Oshima Island伊豆大島近海23:20 JSTconfirmedM2.7Depth: 0 km
- 震度1Adjacent Sea of Izu-Oshima Island伊豆大島近海23:28 JSTconfirmedM2.5Depth: 10 km
- 震度1Adjacent Sea of Izu-Oshima Island伊豆大島近海23:33 JSTconfirmedM2.3Depth: 10 km