Reviewed by USGSChile40y ago
M4.9 earthquake 30 km S of Antofagasta, Chile
Sunday, March 15, 1987, 06:17:51 UTC · 23.925°S, 70.379°W
A magnitude 4.9 earthquake struck 30 km S of Antofagasta, Chile on Sunday, March 15, 1987, 06:17:51 UTC, at a depth of 47.8 km (shallow). It is the strongest earthquake within 300 km since an M5.5 on March 15, 1987.
- Magnitude
- 4.9
- Light · mb
- Depth
- 48 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
338 tons of TNT
That is about 1/45 of the Hiroshima bomb. A magnitude 5.0 releases about 1 times more energy.
Tectonic setting
107 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
48 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 M6.1 on March 22, 1987. 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 241 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.2121 km SSE of San Pedro de Atacama, ChileDecember 9, 1950 · 251 km E of this epicenter
- 8.060 km W of Diego de Almagro, ChileDecember 4, 1918 · 283 km S of this epicenter
- 7.79 km SSW of Taltal, ChileDecember 28, 1966 · 174 km S of this epicenter
- 7.684 km SSE of Antofagasta, ChileMarch 5, 1987 · 56 km SE of this epicenter
- 7.583 km NNE of Taltal, ChileJuly 13, 1936 · 91 km S of this epicenter
- 7.550 km WNW of Diego de Almagro, ChileJune 8, 1909 · 248 km S of this epicenter
- 7.454 km WSW of Diego de Almagro, ChileOctober 4, 1983 · 291 km S of this epicenter
- 7.334 km NE of Tocopilla, ChileDecember 21, 1967 · 232 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 28 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 2,403 recorded deaths. The most severe:
- 1877M8.3
Off North Coast
10 May 1877 · 270 km away · intensity XI
2,385 deaths$2 million damagetsunami
- 1983M7.3
Northern: Copoapo-Chanaral
4 Oct 1983 · 291 km away · intensity VII
5 deaths$1 million damagetsunami
- 1953M7.4
Northern
7 Dec 1953 · 266 km away
3 deaths$7 million damage
- 1966M7.8
Taltal, Catalina
28 Dec 1966 · 178 km away · intensity VIII
3 deathsUnder $1 million damagetsunami
- 1946M7.9
Northern
2 Aug 1946 · 287 km away
2 deathsSevere damage ($5–24M)tsunami
- 1967M7.5
Northern
21 Dec 1967 · 263 km away
1 deathModerate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.