M7.2 earthquake 29 km SSE of Pimampiro, Ecuador

Friday, March 6, 1987, 04:10:41 UTC · 0.151°N, 77.821°W

A magnitude 7.2 earthquake struck 29 km SSE of Pimampiro, Ecuador on Friday, March 6, 1987, 04:10:41 UTC, at a depth of 10.0 km (shallow). It is the strongest earthquake within 300 km since an M7.7 on December 12, 1979.

Magnitude: 7.2; Major · mw
Depth: 10 km; Shallow
Felt reports: 0; Did You Feel It?
Est. shaking: VII; Very strong (ShakeMap)
PAGER alert: None; Not issued
Tsunami: No flag; USGS feed

Outlined circle: this earthquakeDashed circle: 200 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

951 kilotons of TNT

That is about 63 times the Hiroshima bomb. It released about 1,995 times the energy of a magnitude 5.0.

Tectonic setting

17 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 200 km

USGS lists 13 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M6.0 on March 6, 1987. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.

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:

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 37 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 124,938 recorded deaths. The most severe:

1868M7.7
Guayaquil,Ibarra; Colombia: San Pablo
16 Aug 1868 · 44 km away · intensity X
70,000 deathsExtreme damage ($25M+)
1797M8.3
Riobamba, Quito, Cuzco; Peru; Colombia
4 Feb 1797 · 220 km away · intensity XI
40,000 deathsExtreme damage ($25M+)tsunami
1949M6.5
Tungurahua
5 Aug 1949 · 163 km away
6,000 deaths$8 million damage
1987M7.2
Napo Province, Quito, Tulcan
6 Mar 1987 · 9 km away
5,000 deaths$1.5 billion damage
1906M8.8
Off Coast
31 Jan 1906 · 194 km away · intensity IX
1,000 deathsSevere damage ($5–24M)tsunami
1757M7.0
Cotopaxi,Tungurahua, Latacunga
22 Feb 1757 · 145 km away · intensity IX
1,000 deathsSevere damage ($5–24M)

NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.

Nearby trackers