Reviewed by USGSArgentina31y ago
M3.9 earthquake 81 km W of San Antonio de los Cobres, Argentina
Thursday, January 18, 1996, 07:32:12 UTC · 24.196°S, 67.120°W
A magnitude 3.9 earthquake struck 81 km W of San Antonio de los Cobres, Argentina on Thursday, January 18, 1996, 07:32:12 UTC, at a depth of 100.0 km (intermediate).
- Magnitude
- 3.9
- Minor · mb
- Depth
- 100 km
- Intermediate
- 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: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
11 tons of TNT
That is about 1/1,410 of the Hiroshima bomb. A magnitude 5.0 releases about 45 times more energy.
Tectonic setting
298 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: intermediate
100 km
Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.
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 50 km
USGS lists 2 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M3.9 on January 27, 1996. 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 308 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.2121 km SSE of San Pedro de Atacama, ChileDecember 9, 1950 · 84 km W of this epicenter
- 7.187 km SSE of Antofagasta, ChileJuly 8, 1942 · 297 km W of this epicenter
- 7.087 km W of Abra Pampa, ArgentinaMay 24, 1993 · 179 km N of this epicenter
- 7.052 km W of Abra Pampa, ArgentinaApril 1, 1987 · 184 km NE of this epicenter
- 6.930 km SSE of Santa Clara, ArgentinaAugust 25, 1948 · 266 km E of this epicenter
- 6.999 km WNW of San Antonio de los Cobres, ArgentinaFebruary 21, 1971 · 47 km N of this epicenter
- 6.840 km SE of San Pedro de Atacama, ChileAugust 3, 1962 · 140 km NW of this epicenter
- 6.788 km WNW of El Aguilar, ArgentinaSeptember 1, 1987 · 141 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 12 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 37 recorded deaths. The most severe:
- 1930M6.1
La Poma
24 Dec 1930 · 199 km away · intensity VIII
31 deathsSevere damage ($5–24M)
- 1953M7.4
Northern
7 Dec 1953 · 284 km away
3 deaths$7 million damage
- 1936M7.3
Taltal
13 Jul 1936 · 294 km away
1 deathModerate damage ($1–5M)tsunami
- 1971M6.3
Catalina, Antofagasta
17 Jun 1971 · 255 km away · intensity V
1 deathModerate damage ($1–5M)
- 1950M8.0
Chile-Argentina
9 Dec 1950 · 87 km away · intensity VII
1 death
- 1844M6.5
Salta, Jujuy, Tucuman
19 Oct 1844 · 144 km away · intensity VII
Severe damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.