Reviewed by USGSChile16y ago
M4.4 earthquake 36 km SW of Constitución, Chile
Saturday, July 17, 2010, 01:39:40 UTC · 35.532°S, 72.732°W
A magnitude 4.4 earthquake struck 36 km SW of Constitución, Chile on Saturday, July 17, 2010, 01:39:40 UTC, at a depth of 34.0 km (shallow).
- Magnitude
- 4.4
- Light · mb
- Depth
- 34 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
60 tons of TNT
That is about 1/251 of the Hiroshima bomb. A magnitude 5.0 releases about 8 times more energy.
Tectonic setting
101 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
34 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 1 M2.5+ earthquake within 50 km in the following 30 days; the largest was M4.4 on August 6, 2010. 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 614 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 9.51960 Great Chilean Earthquake (Valdivia Earthquake)May 22, 1960 · 296 km S of this epicenter
- 8.82010 Maule, Chile EarthquakeFebruary 27, 2010 · 67 km S of this epicenter
- 8.14 km ESE of Cañete, ChileMay 21, 1960 · 261 km S of this epicenter
- 8.025 km WSW of Valparaíso, ChileMarch 3, 1985 · 278 km N of this epicenter
- 7.826 km WNW of San Carlos, ChileJanuary 25, 1939 · 97 km SE of this epicenter
- 7.838 km WNW of Traiguén, ChileMay 22, 1960 · 283 km S of this epicenter
- 7.730 km NNE of Constitución, ChileDecember 1, 1928 · 65 km NE of this epicenter
- 7.744 km SSE of Cañete, ChileMay 10, 1975 · 298 km S of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 38 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 37,508 recorded deaths. The most severe:
- 1939M8.3
Chillan
25 Jan 1939 · 91 km away · intensity X
30,000 deaths$920 million damagetsunami
- 1906M8.2
South Central
17 Aug 1906 · 289 km away · intensity XI
4,000 deaths$100 million damagetsunami
- 1960M9.5
Puerto Montt, Valdivia
22 May 1960 · 296 km away · intensity XII
2,226 deaths$1.0 billion damagetsunami
- 2010M8.8
Maule, Concepcion, Talcahuano
27 Feb 2010 · 67 km away · intensity IX
558 deaths$30 billion damagetsunami
- 1928M7.6
Talca, Chillan, Santiago, San Fernando
1 Dec 1928 · 89 km away · intensity IX
279 deathsSevere damage ($5–24M)tsunami
- 1985M8.0
Central Coast, San Antonio, Valparaiso
3 Mar 1985 · 283 km away · intensity VIII
180 deaths$1.5 billion damagetsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.