M7.5 earthquake 39 km NW of Yurimaguas, Peru

Monday, September 26, 2005, 01:55:37 UTC · 5.678°S, 76.398°W

A magnitude 7.5 earthquake struck 39 km NW of Yurimaguas, Peru on Monday, September 26, 2005, 01:55:37 UTC, at a depth of 115.0 km (intermediate). USGS received 193 “Did You Feel It?” reports, with a maximum reported intensity of VIII (severe). It is the strongest earthquake within 300 km since an M7.5 on September 28, 1906.

Magnitude: 7.5; Major · mwb
Depth: 115 km; Intermediate
Felt reports: 193; Max intensity VIII
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

2.7 megatons of TNT

That is about 178 times the Hiroshima bomb. It released about 5,623 times the energy of a magnitude 5.0.

Tectonic setting

228 km

from the nearest mapped plate boundary, between the Sunda and Australian plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.

Depth: intermediate

115 km

Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.

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
Lima, Lima Provincias, Peru	IV · Light	73	719 km
Bogotá, Bogotá, Colombia	III · Weak	19	1173 km
Huánuco, Huánuco, Peru	VI · Strong	15	483 km
Trujillo, La Libertad, Peru	IV · Light	11	412 km
Cajamarca, Cajamarca, Peru	IV · Light	8	308 km
Quito, Pichincha, Ecuador	III · Weak	8	660 km
Manaus, Amazonas, Brazil	III · Weak	5	1843 km
Chiclayo, Lambayeque, Peru	IV · Light	4	415 km
Manta, Manabí, Ecuador	III · Weak	4	718 km
Jaén, Cajamarca, Peru	VIII · Severe	3	290 km
Moyobamba, San Martín, Peru	VIII · Severe	3	136 km
Iquitos, Loreto, Peru	VI · Strong	3	429 km

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 1 M2.5+ earthquake within 200 km in the following 30 days; the largest was M4.1 on September 26, 2005. 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.

4.17 km W of Tabalosos, Peru21y ago · 85 km SW of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 153 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 12 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 325 recorded deaths. The most severe:

1990M6.5
Moyabamba-Riojo
30 May 1990 · 99 km away · intensity VI
200 deaths$1 million damage
1991M6.7
Rioja, Moyobamba, Nueva Cajamarca
5 Apr 1991 · 84 km away · intensity VII
53 deathsSevere damage ($5–24M)
1928M7.3
Chacahpoyas,Huancabamba,Cajamarca,Pinpincos
14 May 1928 · 252 km away · intensity X
29 deathsSevere damage ($5–24M)
1968M6.8
San Martin,Moyobamba,Yantalo,Rioja,Lamas
19 Jun 1968 · 77 km away
15 deathsUnder $1 million damage
1972M6.1
Juanjui
20 Mar 1972 · 132 km away · intensity IX
12 deaths$20 million damage
1983M6.5
Chimbote
12 Apr 1983 · 210 km away
10 deathsUnder $1 million damage

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

Nearby trackers