Reviewed by USGSChile10y ago
M4.3 earthquake 29 km WSW of Ovalle, Chile
Friday, October 21, 2016, 19:02:32 UTC · 30.707°S, 71.477°W
A magnitude 4.3 earthquake struck 29 km WSW of Ovalle, Chile on Friday, October 21, 2016, 19:02:32 UTC, at a depth of 42.3 km (shallow).
- Magnitude
- 4.3
- Light · mwr
- Depth
- 42 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
43 tons of TNT
That is about 1/354 of the Hiroshima bomb. A magnitude 5.0 releases about 11 times more energy.
Tectonic setting
109 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
42 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 2 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.3 on October 29, 2016. 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 786 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.348 km W of Illapel, ChileSeptember 16, 2015 · 98 km S of this epicenter
- 8.2The 1906 Valparaiso, Chile EarthquakeAugust 17, 1906 · 188 km S of this epicenter
- 8.145 km NNW of Illapel, ChileApril 6, 1943 · 63 km S of this epicenter
- 8.025 km WSW of Valparaíso, ChileMarch 3, 1985 · 273 km S of this epicenter
- 7.819 km NNE of Hacienda La Calera, ChileJuly 9, 1971 · 214 km S of this epicenter
- 7.47 km SSE of La Ligua, ChileMarch 28, 1965 · 203 km S of this epicenter
- 7.419 km S of Valparaíso, ChileMarch 4, 1985 · 279 km S of this epicenter
- 7.136 km SW of Monte Patria, ChileOctober 15, 1997 · 35 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 52 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 14,785 recorded deaths. The most severe:
- 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 · 260 km away · intensity XI
4,000 deaths$100 million damagetsunami
- 1965M7.3
Central
28 Mar 1965 · 190 km away
400 deaths$125 million damage
- 1985M8.0
Central Coast, San Antonio, Valparaiso
3 Mar 1985 · 271 km away · intensity VIII
180 deaths$1.5 billion damagetsunami
- 1971M7.8
Central
9 Jul 1971 · 201 km away · intensity IX
83 deaths$236 million damagetsunami
- 1822M8.5
Valparaiso, Quillota, Concon, Aconcagua
20 Nov 1822 · 260 km away · intensity XI
72 deathsExtreme damage ($25M+)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.