Reviewed by USGSPeru25y ago
M4.4 earthquake 23 km ESE of Atico, Peru
Saturday, July 28, 2001, 19:45:04 UTC · 16.316°S, 73.435°W
A magnitude 4.4 earthquake struck 23 km ESE of Atico, Peru on Saturday, July 28, 2001, 19:45:04 UTC, at a depth of 37.3 km (shallow).
- Magnitude
- 4.4
- Light · mb
- Depth
- 37 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
60 tons of TNT
That is about 1/251 of the Hiroshima bomb. A magnitude 5.0 releases about 8 times more energy.
Tectonic setting
124 km
from the nearest mapped plate boundary, between the Nazca and Altiplano plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
37 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 3 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.7 on August 14, 2001. 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 348 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.46 km SSW of Atico, PeruJune 23, 2001 · 23 km W of this epicenter
- 8.121 km NNE of Minas de Marcona, PeruAugust 24, 1942 · 222 km NW of this epicenter
- 7.737 km SSW of Atico, PeruAugust 6, 1913 · 40 km SW of this epicenter
- 7.760 km SW of Changuillo, PeruNovember 12, 1996 · 281 km NW of this epicenter
- 7.651 km SW of Punta de Bombón, PeruJuly 7, 2001 · 199 km SE of this epicenter
- 7.235 km N of El Cardo, PeruOctober 11, 1922 · 78 km E of this epicenter
- 7.212 km NNE of Cono Norte, PeruFebruary 26, 1914 · 201 km E of this epicenter
- 7.121 km SSE of Nazca, PeruJanuary 15, 1960 · 211 km NW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 32 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 1,059 recorded deaths. The most severe:
- 1784M8.0
Arequipa,Camana,Moquegua,Tambo
13 May 1784 · 154 km away · intensity X
383 deathsSevere damage ($5–24M)tsunami
- 1821
Camana, Ocona, Caraveli
10 Jul 1821 · 55 km away · intensity VIII
162 deathsSevere damage ($5–24M)
- 1913M6.3
Amyaraes, Abancay, Casaya, Soraya
4 Nov 1913 · 242 km away · intensity X
150 deathsSevere damage ($5–24M)
- 2001M8.4
Arequipa, Moquegua, Tacna, Ayacucho
23 Jun 2001 · 23 km away · intensity VIII
103 deaths$200 million damagetsunami
- 1991M4.7
Maca, Chivay, Yanque
23 Jul 1991 · 211 km away · intensity V
92 deathsModerate damage ($1–5M)
- 1960M7.8
Arequipa,Chuquibamba,Caraveli,Cotahuasi
13 Jan 1960 · 97 km away · intensity X
63 deathsSevere damage ($5–24M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.