Reviewed by USGSChile28y ago
M4.2 earthquake 44 km WSW of Illapel, Chile
Sunday, December 6, 1998, 05:07:00 UTC · 31.752°S, 71.619°W
A magnitude 4.2 earthquake struck 44 km WSW of Illapel, Chile on Sunday, December 6, 1998, 05:07:00 UTC, at a depth of 30.6 km (shallow).
- Magnitude
- 4.2
- Light · md
- Depth
- 31 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 earthquakeDashed circle: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
30 tons of TNT
That is about 1/500 of the Hiroshima bomb. A magnitude 5.0 releases about 16 times more energy.
Tectonic setting
102 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
31 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 lists 7 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.6 on January 3, 1999. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 4.644 km W of Illapel, Chile28y ago · 15 km N of this epicenter
- 3.757 km NW of La Ligua, Chile28y ago · 32 km S of this epicenter
- 4.163 km WNW of Illapel, Chile28y ago · 39 km NW of this epicenter
- 3.5Near the coast of Valparaiso, Chile28y ago · 49 km S of this epicenter
- 3.751 km NNW of La Ligua, Chile28y ago · 34 km SE of this epicenter
- 4.379 km W of Illapel, Chile28y ago · 40 km W of this epicenter
- 3.759 km WNW of La Ligua, Chile28y ago · 48 km S of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 492 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.2The 1906 Valparaiso, Chile EarthquakeAugust 17, 1906 · 75 km S of this epicenter
- 8.145 km NNW of Illapel, ChileApril 6, 1943 · 59 km NE of this epicenter
- 8.025 km WSW of Valparaíso, ChileMarch 3, 1985 · 156 km S of this epicenter
- 7.819 km NNE of Hacienda La Calera, ChileJuly 9, 1971 · 105 km SE of this epicenter
- 7.47 km SSE of La Ligua, ChileMarch 28, 1965 · 93 km SE of this epicenter
- 7.419 km S of Valparaíso, ChileMarch 4, 1985 · 162 km S of this epicenter
- 7.237 km S of San Antonio, ChileMarch 18, 1931 · 242 km S of this epicenter
- 7.259 km S of San Antonio, ChileApril 9, 1985 · 265 km S of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 47 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 28,783 recorded deaths. The most severe:
- 1861
Mendoza, San Luiz
20 Mar 1861 · 289 km away · intensity IX
14,000 deathsExtreme damage ($25M+)tsunami
- 1944M6.9
San Juan Province
15 Jan 1944 · 298 km away · intensity IX
10,000 deaths$100 million damage
- 1906M8.2
South Central
17 Aug 1906 · 143 km away · intensity XI
4,000 deaths$100 million damagetsunami
- 1965M7.3
Central
28 Mar 1965 · 82 km away
400 deaths$125 million damage
- 1985M8.0
Central Coast, San Antonio, Valparaiso
3 Mar 1985 · 154 km away · intensity VIII
180 deaths$1.5 billion damagetsunami
- 1971M7.8
Central
9 Jul 1971 · 92 km away · intensity IX
83 deaths$236 million damagetsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.