Reviewed by USGSEcuador40y ago
M4.3 earthquake 43 km ESE of Cayambe, Ecuador
Monday, March 16, 1987, 07:31:49 UTC · 0.100°S, 77.776°W
A magnitude 4.3 earthquake struck 43 km ESE of Cayambe, Ecuador on Monday, March 16, 1987, 07:31:49 UTC, at a depth of 10.0 km (shallow).
- Magnitude
- 4.3
- Light · mb
- Depth
- 10 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- IV
- Light (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 50 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
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
35 km
from the nearest mapped plate boundary, between the North Andes and South American plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
10 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 M3.7 on March 24, 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 101 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.81906 Ecuador-Colombia EarthquakeJanuary 31, 1906 · 212 km NW of this epicenter
- 7.812 km SE of Pedernales, EcuadorMay 14, 1942 · 245 km W of this epicenter
- 7.756 km NW of Valdez, EcuadorDecember 12, 1979 · 258 km NW of this epicenter
- 7.6near the coast of EcuadorJanuary 19, 1958 · 227 km NW of this epicenter
- 7.229 km SSE of Pimampiro, EcuadorMarch 6, 1987 · 28 km N of this epicenter
- 7.07 km NNE of Tosagua, EcuadorJanuary 16, 1956 · 280 km W of this epicenter
- 6.951 km NW of Valdez, EcuadorFebruary 1, 1958 · 252 km NW of this epicenter
- 6.824 km NNE of Esmeraldas, EcuadorJanuary 19, 1958 · 241 km NW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 35 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 124,589 recorded deaths. The most severe:
- 1868M7.7
Guayaquil,Ibarra; Colombia: San Pablo
16 Aug 1868 · 64 km away · intensity X
70,000 deathsExtreme damage ($25M+)
- 1797M8.3
Riobamba, Quito, Cuzco; Peru; Colombia
4 Feb 1797 · 198 km away · intensity XI
40,000 deathsExtreme damage ($25M+)tsunami
- 1949M6.5
Tungurahua
5 Aug 1949 · 139 km away
6,000 deaths$8 million damage
- 1987M7.2
Napo Province, Quito, Tulcan
6 Mar 1987 · 20 km away
5,000 deaths$1.5 billion damage
- 1906M8.8
Off Coast
31 Jan 1906 · 212 km away · intensity IX
1,000 deathsSevere damage ($5–24M)tsunami
- 1757M7.0
Cotopaxi,Tungurahua, Latacunga
22 Feb 1757 · 128 km away · intensity IX
1,000 deathsSevere damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.