Reviewed by USGS4y ago
M7.3 earthquake in Flores Sea
Tuesday, December 14, 2021, 03:20:23 UTC · 7.603°S, 122.227°E
A magnitude 7.3 earthquake struck in Flores Sea on Tuesday, December 14, 2021, 03:20:23 UTC, at a depth of 14.3 km (shallow). USGS received 38 “Did You Feel It?” reports, with a maximum reported intensity of IX (violent). The USGS PAGER alert is green: low likelihood of casualties and damage. It is the strongest earthquake within 300 km since an M7.5 on November 11, 2004.
Tsunami flagUSGS sets this flag for large events in oceanic regions so tsunami warning centers review them. It does not by itself mean a tsunami occurred. Check tsunami.gov and local authorities for official messages.
- Magnitude
- 7.3
- Major · mww
- Depth
- 14 km
- Shallow
- Felt reports
- 38
- Max intensity IX
- Est. shaking
- V
- Moderate (ShakeMap)
- PAGER alert
- Green
- Impact estimate
- Tsunami
- Flag
- Check tsunami.gov
Outlined circle: this earthquakeDashed circle: 200 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
1.3 megatons of TNT
That is about 89 times the Hiroshima bomb. It released about 2,818 times the energy of a magnitude 5.0.
Tectonic setting
39 km
from the nearest mapped plate boundary, between the Banda Sea and Timor plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
14 km
Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.
Did You Feel It?
Where it was felt
Reports sent by people to USGS, grouped by place (most reports first). Intensity uses the Modified Mercalli scale (I–X): what people felt, not the magnitude.
| Place | Intensity | Reports | Distance |
|---|---|---|---|
| Maumere, Nusa Tenggara Timur, Indonesia | VIII · Severe | 7 | 113 km |
| Makasar, Sulawesi Selatan, Indonesia | IV · Light | 6 | 414 km |
| Ruteng, Nusa Tenggara Timur, Indonesia | VIII · Severe | 4 | 223 km |
| Denpasar, Bali, Indonesia | I · Not felt | 2 | 781 km |
| Kuta, Bali, Indonesia | I · Not felt | 2 | 787 km |
| Ende, Nusa Tenggara Timur, Indonesia | IX · Violent | 1 | 153 km |
| Kendari, Sulawesi Tenggara, Indonesia | VI · Strong | 1 | 404 km |
| Bima, Nusa Tenggara Barat, Indonesia | V · Moderate | 1 | 398 km |
| Sombaopu, Sulawesi Selatan, Indonesia | V · Moderate | 1 | 411 km |
| Oecussi, Oecussi, East Timor | III · Weak | 1 | 295 km |
| Kupang, Nusa Tenggara Timur, Indonesia | III · Weak | 1 | 320 km |
| Singkang, Sulawesi Selatan, Indonesia | III · Weak | 1 | 453 km |
USGS PAGER estimate
Who was exposed to shaking
Modelled from the ShakeMap and population data. Alert level green: low likelihood of casualties and damage.
- VI · Strong shaking
- 1,400 people
- V · Moderate shaking
- 318,000 people
- IV · Light shaking
- 3.2 million people
- III · Weak shaking
- 13 million people
- II · Weak shaking
- 3.8 million people
Estimated shaking in nearby towns
- RiangkrokoPopulation 0V · Moderate
- RiangpuhoPopulation 0V · Moderate
- TurubeangPopulation 0V · Moderate
- PemanaPopulation 0V · Moderate
- ParumaanPopulation 0V · Moderate
- KotenPopulation 0V · Moderate
- KupangcapitalPopulation 282,000III · Weak
- MakassarcapitalPopulation 1.3 millionIII · Weak
After the main event
Aftershocks within 200 km
USGS lists 42 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M5.8 on December 14, 2021. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 4.4152 km S of Katabu, Indonesia4y ago · 149 km N of this epicenter
- 4.668 km N of Maumere, Indonesia4y ago · 46 km S of this epicenter
- 4.3140 km NNW of Pante Makasar, Timor Leste4y ago · 174 km E of this epicenter
- 4.3133 km NNW of Pante Makasar, Timor Leste4y ago · 187 km E of this epicenter
- 4.2216 km NE of Maumere, Indonesia4y ago · 165 km E of this epicenter
- 4.1145 km N of Maumere, Indonesia4y ago · 34 km N of this epicenter
- 4.3158 km N of Maumere, Indonesia4y ago · 49 km NW of this epicenter
- 4.9125 km SSW of Katabu, Indonesia4y ago · 178 km N of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 530 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.9169 km NNE of Maumere, IndonesiaJune 17, 1996 · 65 km NE of this epicenter
- 7.837 km WNW of Maumere, IndonesiaDecember 12, 1992 · 104 km S of this epicenter
- 7.563 km NW of Maubara, Timor LesteNovember 11, 2004 · 297 km E of this epicenter
- 7.270 km SE of Maumere, IndonesiaOctober 20, 1938 · 164 km S of this epicenter
- 7.1135 km NNE of Labuan Bajo, IndonesiaMay 24, 1990 · 207 km W of this epicenter
- 7.0199 km SSW of Katabu, IndonesiaMarch 3, 1927 · 107 km N of this epicenter
- 7.0194 km SE of Baubau, IndonesiaAugust 6, 1914 · 226 km NE of this epicenter
- 7.0150 km NNE of Maumere, IndonesiaFebruary 27, 2015 · 48 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 15 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 2,956 recorded deaths. The most severe:
- 1992M7.8
Flores Region, Maumere, Babi
12 Dec 1992 · 104 km away · intensity XI
2,500 deaths$100 million damagetsunami
- 1896
Timor: Alor Island
18 Apr 1896 · 287 km away · intensity VIII
250 deathsModerate damage ($1–5M)
- 1987M6.5
Timor: Pantar, Mount Sirung
26 Nov 1987 · 224 km away
125 deaths$5 million damagetsunami
- 2004M7.5
Kepulauan Alor
11 Nov 2004 · 297 km away
34 deathsSevere damage ($5–24M)tsunami
- 1991M6.5
Timor: Kalabahi, Dili
4 Jul 1991 · 276 km away
28 deaths$8 million damage
- 1982M5.9
Flores Island: Eastern
25 Dec 1982 · 129 km away
13 deaths$1 million damagetsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.