Reviewed by USGSChile16y ago
M4.8 earthquake 48 km WNW of Constitución, Chile
Thursday, July 15, 2010, 22:57:01 UTC · 35.160°S, 72.905°W
A magnitude 4.8 earthquake struck 48 km WNW of Constitución, Chile on Thursday, July 15, 2010, 22:57:01 UTC, at a depth of 25.3 km (shallow). USGS received 4 “Did You Feel It?” reports, with a maximum reported intensity of IV (light). It is the strongest earthquake within 300 km since an M5.4 on July 15, 2010.
- Magnitude
- 4.8
- Light · mb
- Depth
- 25 km
- Shallow
- Felt reports
- 4
- Max intensity IV
- 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
239 tons of TNT
That is about 1/63 of the Hiroshima bomb. A magnitude 5.0 releases about 2 times more energy.
Tectonic setting
76 km
from the nearest mapped plate boundary, between the Nazca and South American plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
25 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
Reports sent by people to USGS, grouped by place (most reports first). Intensity uses the Modified Mercalli scale (I–X): what people felt, not the magnitude.
| Place | Intensity | Reports | Distance |
|---|---|---|---|
| Curicó, Maule, Chile | II · Weak | 2 | 155 km |
| Talca, Maule, Chile | IV · Light | 1 | 119 km |
| Temuco, Araucanía, Chile | II · Weak | 1 | 398 km |
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 M4.4 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 610 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.82010 Maule, Chile EarthquakeFebruary 27, 2010 · 107 km S of this epicenter
- 8.14 km ESE of Cañete, ChileMay 21, 1960 · 299 km S of this epicenter
- 8.025 km WSW of Valparaíso, ChileMarch 3, 1985 · 244 km NE of this epicenter
- 7.826 km WNW of San Carlos, ChileJanuary 25, 1939 · 141 km SE of this epicenter
- 7.730 km NNE of Constitución, ChileDecember 1, 1928 · 59 km E of this epicenter
- 7.7103 km NW of Constitución, ChileJanuary 30, 1914 · 57 km NW of this epicenter
- 7.523 km SE of Chiguayante, ChileMay 6, 1953 · 215 km S of this epicenter
- 7.419 km S of Valparaíso, ChileMarch 4, 1985 · 245 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 36 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 35,232 recorded deaths. The most severe:
- 1939M8.3
Chillan
25 Jan 1939 · 135 km away · intensity X
30,000 deaths$920 million damagetsunami
- 1906M8.2
South Central
17 Aug 1906 · 254 km away · intensity XI
4,000 deaths$100 million damagetsunami
- 2010M8.8
Maule, Concepcion, Talcahuano
27 Feb 2010 · 107 km away · intensity IX
558 deaths$30 billion damagetsunami
- 1928M7.6
Talca, Chillan, Santiago, San Fernando
1 Dec 1928 · 84 km away · intensity IX
279 deathsSevere damage ($5–24M)tsunami
- 1985M8.0
Central Coast, San Antonio, Valparaiso
3 Mar 1985 · 251 km away · intensity VIII
180 deaths$1.5 billion damagetsunami
- 1822M8.5
Valparaiso, Quillota, Concon, Aconcagua
20 Nov 1822 · 254 km away · intensity XI
72 deathsExtreme damage ($25M+)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.