Reviewed by USGSItaly108y ago
M5.7 earthquake 18 km SSE of Anzio, Italy
Wednesday, October 22, 1919, 06:05:57 UTC · 41.295°N, 12.673°E
A magnitude 5.7 earthquake struck 18 km SSE of Anzio, Italy on Wednesday, October 22, 1919, 06:05:57 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M5.7 on April 26, 1917.
- Magnitude
- 5.7
- Moderate · mw
- Depth
- 15 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquake
In context
How big was it, and why here?
Energy released
5 kilotons of TNT
That is about 1/3 of the Hiroshima bomb. It released about 11 times the energy of a magnitude 5.0.
Tectonic setting
264 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
15 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
No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.
I felt it — report to USGS ↗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 75 km
USGS has not published any M2.5+ earthquake within 75 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 17 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 6.74 km WNW of San Benedetto dei Marsi, ItalyJanuary 13, 1915 · 111 km NE of this epicenter
- 6.572 km WSW of Cittadella del Capo, ItalyAugust 1, 1910 · 296 km SE of this epicenter
- 6.025 km W of San Marco, ItalyJuly 7, 1915 · 200 km SE of this epicenter
- 5.91 km ENE of Cairano, ItalyJune 7, 1910 · 232 km E of this epicenter
- 5.89 km ESE of Marina di Camerota, ItalyApril 5, 1911 · 278 km SE of this epicenter
- 5.76 km SW of Monterchi, ItalyApril 26, 1917 · 245 km N of this epicenter
- 5.53 km E of Monteleone di Spoleto, ItalyNovember 16, 1916 · 153 km N of this epicenter
- 5.50 km SSE of Sorano, ItalySeptember 10, 1919 · 173 km NW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 50 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 96,330 recorded deaths. The most severe:
- 1703
Central Apennino, Norcia, L'Aquila, Perugia
14 Jan 1703 · 169 km away · intensity XI
40,000 deathsExtreme damage ($25M+)
- 1915M7.5
Marsica, Avezzano, Abruzzi
13 Jan 1915 · 104 km away · intensity XI
29,978 deaths$60 million damage
- 1703M6.7
L'Aquila (Aquila)
2 Feb 1703 · 137 km away · intensity XI
10,000 deathsSevere damage ($5–24M)tsunami
- 1805
Molise, Rosolone, Napoli (Naples), Isernia
26 Jul 1805 · 170 km away · intensity XI
5,600 deathsExtreme damage ($25M+)
- 1731M6.3
Foggia
20 Mar 1731 · 237 km away · intensity X
3,600 deathsSevere damage ($5–24M)tsunami
- 1883
Ischia Is: Casamicciola, Forino, Lacco Ameno
28 Jul 1883 · 122 km away · intensity X
2,313 deathsExtreme damage ($25M+)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.