Reviewed by USGSArgentina43y ago
M5.1 earthquake 22 km NW of Añatuya, Argentina
Thursday, December 22, 1983, 11:53:37 UTC · 28.309°S, 62.990°W
A magnitude 5.1 earthquake struck 22 km NW of Añatuya, Argentina on Thursday, December 22, 1983, 11:53:37 UTC, at a depth of 592.8 km (deep). It is the strongest earthquake within 300 km since an M5.9 on December 21, 1983.
- Magnitude
- 5.1
- Moderate · mb
- Depth
- 593 km
- Deep
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
674 tons of TNT
That is about 1/22 of the Hiroshima bomb. It released about 1 times the energy of a magnitude 5.0.
Tectonic setting
769 km
from the nearest mapped plate boundary, between the Altiplano and South American plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: deep
593 km
Deep earthquakes (over 300 km) happen deep inside subducting plates. They rarely cause damage, but can be felt faintly over very large distances.
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 lists 1 M2.5+ earthquake within 75 km in the following 30 days; the largest was M4.8 on December 29, 1983. 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 23 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.331 km SE of Villa Atamisqui, ArgentinaDecember 7, 1912 · 68 km SW of this epicenter
- 7.221 km SSE of Taco Pozo, ArgentinaDecember 8, 1962 · 280 km N of this epicenter
- 7.144 km WNW of Quimilí, ArgentinaAugust 14, 1950 · 90 km N of this epicenter
- 7.148 km NNW of Suncho Corral, ArgentinaJune 21, 1916 · 104 km NW of this epicenter
- 6.938 km SE of Suncho Corral, ArgentinaDecember 21, 1983 · 22 km NW of this epicenter
- 6.739 km NNE of Suncho Corral, ArgentinaSeptember 9, 1967 · 80 km N of this epicenter
- 6.410 km SW of El Hoyo, ArgentinaSeptember 29, 1962 · 139 km N of this epicenter
- 6.341 km S of El Hoyo, ArgentinaDecember 9, 1964 · 103 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 6 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1908M6.5
Cordoba
22 Sep 1908 · 284 km away · intensity VII
Moderate damage ($1–5M)
- 1817
Santiago Del Estero Province
4 Jul 1817 · 152 km away · intensity VIII
Moderate damage ($1–5M)
- 1826
Candelaria, Trancas, Zarate, El Tala
19 Jan 1826 · 246 km away · intensity VII
Moderate damage ($1–5M)
- 1892
Catamarca
21 Mar 1892 · 236 km away · intensity VII
Limited damage (under $1M)
- 1912M7.5
Santiago Del Estero Province
7 Dec 1912 · 90 km away
- 1916M7.5
Argentina
21 Jun 1916 · 21 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.