Reviewed by USGSPeru7y ago
M5.4 earthquake 47 km SSW of Puerto Casma, Peru
Tuesday, November 20, 2018, 06:38:06 UTC · 9.848°S, 78.575°W
A magnitude 5.4 earthquake struck 47 km SSW of Puerto Casma, Peru on Tuesday, November 20, 2018, 06:38:06 UTC, at a depth of 57.4 km (shallow). USGS received 10 “Did You Feel It?” reports, with a maximum reported intensity of IV (light). The USGS PAGER alert is green: low likelihood of casualties and damage. It is the strongest earthquake within 300 km since an M5.6 on April 26, 2015.
- Magnitude
- 5.4
- Moderate · mww
- Depth
- 57 km
- Shallow
- Felt reports
- 10
- Max intensity IV
- Est. shaking
- IV
- Light (ShakeMap)
- PAGER alert
- Green
- Impact estimate
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 75 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
2 kilotons of TNT
That is about 1/8 of the Hiroshima bomb. It released about 4 times the energy of a magnitude 5.0.
Tectonic setting
175 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
57 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
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 | III · Weak | 3 | 302 km |
| San Luis, Lima Provincias, Peru | II · Weak | 2 | 306 km |
| Santa Rosa, Lambayeque, Peru | IV · Light | 1 | 372 km |
| Huaraz, Ancash, Peru | IV · Light | 1 | 133 km |
| Huánuco, Huánuco, Peru | II · Weak | 1 | 262 km |
| Huanchanco, La Libertad, Peru | II · Weak | 1 | 212 km |
| Trujillo, La Libertad, Peru | II · Weak | 1 | 206 km |
USGS PAGER estimate
Who was exposed to shaking
Modelled from the ShakeMap and population data. Alert level green: low likelihood of casualties and damage.
- IV · Light shaking
- 49,000 people
- III · Weak shaking
- 2.3 million people
- II · Weak shaking
- 14 million people
Estimated shaking in nearby towns
- HuarmeyPopulation 16,000IV · Light
- La Caleta CulebrasPopulation 0IV · Light
- Puerto CasmaPopulation 0IV · Light
- CasmaPopulation 0IV · Light
- SamancoPopulation 0III · Weak
- NepenaPopulation 0III · Weak
- TrujillocapitalPopulation 747,000III · Weak
- CallaocapitalPopulation 813,000II · Weak
After the main event
Aftershocks within 75 km
USGS lists 1 M2.5+ earthquake within 75 km in the following 30 days; the largest was M4.5 on November 20, 2018. 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 173 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.221 km SE of Huacho, PeruMay 24, 1940 · 197 km SE of this epicenter
- 8.167 km W of Paramonga, PeruOctober 17, 1966 · 96 km S of this epicenter
- 7.934 km SW of Chimbote, PeruMay 31, 1970 · 71 km NW of this epicenter
- 7.677 km WSW of Callao, PeruOctober 3, 1974 · 282 km S of this epicenter
- 7.5123 km WSW of Puerto Santa, PeruFebruary 21, 1996 · 114 km W of this epicenter
- 7.155 km SW of Santiago de Cao, PeruJune 21, 1937 · 210 km NW of this epicenter
- 7.0179 km WSW of Huarmey, PeruSeptember 3, 1967 · 150 km SW of this epicenter
- 6.928 km W of Paramonga, PeruSeptember 24, 1963 · 104 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 30 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 75,479 recorded deaths. The most severe:
- 1970M7.9
Northern, Pisco, Chiclayo
31 May 1970 · 76 km away · intensity X
66,794 deaths$530 million damagetsunami
- 1746M8.0
Lima, Callao
29 Oct 1746 · 282 km away · intensity XI
5,941 deathsExtreme damage ($25M+)tsunami
- 1725M7.7
Trujillo, Ancash, Lima
7 Jan 1725 · 105 km away · intensity IX
1,500 deathsSevere damage ($5–24M)
- 1946M7.3
Jocaibamba,Cerro Angaschaj,Cerro Sillapata
10 Nov 1946 · 191 km away · intensity XI
800 deathsSevere damage ($5–24M)
- 1940M8.2
Peru
24 May 1940 · 187 km away · intensity X
179 deathsSevere damage ($5–24M)tsunami
- 1966M8.1
Lima,Huacho,Huaura, Chancay,Supe,San Nicolas
17 Oct 1966 · 100 km away · intensity IX
110 deaths$35 million damagetsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.