Reviewed by USGSArgentina28y ago
M3.2 earthquake 46 km NNE of San Martín, Argentina
Tuesday, October 27, 1998, 13:48:26 UTC · 31.020°S, 68.396°W
A magnitude 3.2 earthquake struck 46 km NNE of San Martín, Argentina on Tuesday, October 27, 1998, 13:48:26 UTC, at a depth of 247.8 km (intermediate).
- Magnitude
- 3.2
- Minor · md
- Depth
- 248 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
951 kg of TNT
That is about 1/15,825 of the Hiroshima bomb. A magnitude 5.0 releases about 501 times more energy.
Tectonic setting
403 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: intermediate
248 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 1 M2.5+ earthquake within 50 km in the following 30 days; the largest was M4.1 on November 18, 1998. 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 292 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.145 km NNW of Illapel, ChileApril 6, 1943 · 284 km W of this epicenter
- 7.4San Juan, ArgentinaNovember 23, 1977 · 60 km E of this epicenter
- 7.136 km SW of Monte Patria, ChileOctober 15, 1997 · 269 km W of this epicenter
- 6.94 km ESE of Chimbas, ArgentinaJanuary 15, 1944 · 54 km S of this epicenter
- 6.972 km WNW of Calingasta, ArgentinaJuly 27, 1917 · 159 km W of this epicenter
- 6.88 km W of Nueve de Julio, ArgentinaJune 11, 1952 · 73 km S of this epicenter
- 6.726 km S of Nueve de Julio, ArgentinaDecember 17, 1920 · 98 km S of this epicenter
- 6.725 km SE of Monte Patria, ChileNovember 14, 1927 · 225 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 20 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 24,500 recorded deaths. The most severe:
- 1861
Mendoza, San Luiz
20 Mar 1861 · 202 km away · intensity IX
14,000 deathsExtreme damage ($25M+)tsunami
- 1944M6.9
San Juan Province
15 Jan 1944 · 54 km away · intensity IX
10,000 deaths$100 million damage
- 1920M6.7
Mendoza
17 Dec 1920 · 98 km away · intensity VIII
400 deathsSevere damage ($5–24M)
- 1977M7.5
San Juan Province: Mendoza
23 Nov 1977 · 54 km away · intensity IX
65 deaths$80 million damage
- 1899
La Rioja
12 Apr 1899 · 264 km away · intensity VIII
11 deathsModerate damage ($1–5M)
- 1997M7.1
Pueblo Nuevo, Coquimbo, La Chimba
15 Oct 1997 · 269 km away
8 deaths$48 million damage
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.