Reviewed by USGSArgentina22y ago
M4.5 earthquake 21 km W of Ancasti, Argentina
Friday, September 24, 2004, 09:27:36 UTC · 28.831°S, 65.721°W
A magnitude 4.5 earthquake struck 21 km W of Ancasti, Argentina on Friday, September 24, 2004, 09:27:36 UTC, at a depth of 53.8 km (shallow). It is the strongest earthquake within 300 km since an M6.4 on September 7, 2004.
- Magnitude
- 4.5
- Light · mb
- Depth
- 54 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
85 tons of TNT
That is about 1/178 of the Hiroshima bomb. A magnitude 5.0 releases about 6 times more energy.
Tectonic setting
620 km
from the nearest mapped plate boundary, between the Nazca and South American plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
54 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 50 km
USGS has not published any M2.5+ earthquake within 50 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 122 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 · 212 km E of this epicenter
- 7.148 km NNW of Suncho Corral, ArgentinaJune 21, 1916 · 259 km NE of this epicenter
- 7.032 km NW of Fiambalá, ArgentinaAugust 3, 1920 · 259 km NW of this epicenter
- 7.022 km NW of Añatuya, ArgentinaApril 23, 2000 · 273 km E of this epicenter
- 6.918 km NW of Colonia Dora, ArgentinaMay 10, 1994 · 259 km E of this epicenter
- 6.944 km SSE of Suncho Corral, ArgentinaApril 29, 1994 · 248 km E of this epicenter
- 6.938 km SE of Suncho Corral, ArgentinaDecember 21, 1983 · 259 km E of this epicenter
- 6.739 km NNE of Suncho Corral, ArgentinaSeptember 9, 1967 · 279 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 8 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 12 recorded deaths. The most severe:
- 1899
La Rioja
12 Apr 1899 · 262 km away · intensity VIII
11 deathsModerate damage ($1–5M)
- 2004M6.1
Catamarca
7 Sep 2004 · 31 km away
1 deathLimited damage (under $1M)
- 1908M6.5
Cordoba
22 Sep 1908 · 220 km away · intensity VII
Moderate damage ($1–5M)
- 2002M6.0
Aminga, Anillaco, Agua Blanca, Chuquis
28 May 2002 · 105 km away · intensity VIII
Moderate damage ($1–5M)
- 1817
Santiago Del Estero Province
4 Jul 1817 · 151 km away · intensity VIII
Moderate damage ($1–5M)
- 1898
Catamarca
5 Feb 1898 · 60 km away · intensity VIII
Moderate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.