Reviewed by USGSCroatia5y ago
M4.7 earthquake 3 km W of Petrinja, Croatia
Wednesday, January 6, 2021, 17:01:43 UTC · 45.432°N, 16.242°E
A magnitude 4.7 earthquake struck 3 km W of Petrinja, Croatia on Wednesday, January 6, 2021, 17:01:43 UTC, at a depth of 10.0 km (shallow). USGS received 118 “Did You Feel It?” reports, with a maximum reported intensity of VIII (severe). It is the strongest earthquake within 300 km since an M4.9 on December 29, 2020.
- Magnitude
- 4.7
- Light · mwr
- Depth
- 10 km
- Shallow
- Felt reports
- 118
- Max intensity VIII
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
169 tons of TNT
That is about 1/89 of the Hiroshima bomb. A magnitude 5.0 releases about 3 times more energy.
Tectonic setting
705 km
from the nearest mapped plate boundary, between the Eurasian and African plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
10 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 |
|---|---|---|---|
| Zagreb, Grad Zagreb, Croatia | IV · Light | 14 | 47 km |
| Pécs, Baranya, Hungary | III · Weak | 5 | 170 km |
| Trieste, Friuli-Venezia Giulia, Italy | III · Weak | 4 | 194 km |
| Karlovac, Karlovac, Croatia | IV · Light | 3 | 56 km |
| Ljubljana, Osrednjeslovenska, Slovenia | III · Weak | 3 | 152 km |
| Banja Luka, Republika Srpska, Bosnia and Herzegovina | III · Weak | 3 | 104 km |
| Szigetvár, Baranya, Hungary | III · Weak | 3 | 140 km |
| Virovitica, Virovitica-Podravina, Croatia | IV · Light | 2 | 100 km |
| Gradići, Zagreb, Croatia | IV · Light | 2 | 34 km |
| Sesvete, Grad Zagreb, Croatia | III · Weak | 2 | 47 km |
| Pitomača, Virovitica-Podravina, Croatia | III · Weak | 2 | 96 km |
| Novo Mesto, Jugovžodna Slovenija, Slovenia | III · Weak | 2 | 94 km |
USGS PAGER estimate
Who was exposed to shaking
USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.
After the main event
Aftershocks within 50 km
USGS lists 4 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.4 on January 15, 2021. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 121 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 6.53 km SW of Prato, ItalyMay 6, 1976 · 252 km NW of this epicenter
- 6.42 km WSW of Petrinja, CroatiaDecember 29, 2020 · 1 km SE of this epicenter
- 6.24 km ENE of Baška Voda, CroatiaJanuary 11, 1962 · 237 km S of this epicenter
- 6.22 km SE of Grabovci, CroatiaDecember 29, 1942 · 231 km S of this epicenter
- 6.2CroatiaJanuary 7, 1962 · 251 km S of this epicenter
- 6.1Bosnia and HerzegovinaMarch 15, 1923 · 266 km SE of this epicenter
- 6.11 km WNW of Lestans, ItalyJune 17, 1976 · 274 km W of this epicenter
- 6.14 km ENE of Trn, Bosnia and HerzegovinaOctober 27, 1969 · 103 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 55 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 1,175 recorded deaths. The most severe:
- 1976M6.5
Ne, Balkans Nw: Slovenia: Nw
6 May 1976 · 252 km away · intensity X
978 deaths$3.6 billion damage
- 1763M6.2
Gyor; Czechoslovakia: Komarom
28 Jun 1763 · 293 km away · intensity IX
83 deathsLimited damage (under $1M)
- 1943
Bosnia-Herzegovina
29 Jan 1943 · 139 km away
19 deathsLimited damage (under $1M)
- 1930M6.0
Senigallia
30 Oct 1930 · 278 km away · intensity IX
18 deathsSevere damage ($5–24M)tsunami
- 1969M6.0
Bosnia-Herzegovina: Banja Luka
26 Oct 1969 · 102 km away · intensity VIII
14 deaths$50 million damage
- 1976M6.0
Northeastern
15 Sep 1976 · 255 km away · intensity IX
11 deathsModerate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.