Reviewed by USGSMexico48y ago
M4.4 earthquake 20 km ENE of Vallecitos de Zaragoza, Mexico
Friday, March 16, 1979, 10:10:37 UTC · 17.994°N, 101.148°W
A magnitude 4.4 earthquake struck 20 km ENE of Vallecitos de Zaragoza, Mexico on Friday, March 16, 1979, 10:10:37 UTC, at a depth of 33.0 km (shallow).
- Magnitude
- 4.4
- Light · mb
- Depth
- 33 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
121 km
from the nearest mapped plate boundary, between the Cocos and North American plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
33 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 M5.1 on March 22, 1979. 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 114 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.87 km E of Los Tepames, MexicoJune 18, 1932 · 281 km NW of this epicenter
- 7.621 km ESE of Coalcomán de Vázquez Pallares, MexicoApril 15, 1941 · 209 km W of this epicenter
- 7.68 km ENE of Apantla, MexicoJuly 28, 1957 · 242 km SE of this epicenter
- 7.619 km W of Arteaga, MexicoJune 7, 1911 · 146 km W of this epicenter
- 7.612 km SSE of Vallecitos de Zaragoza, MexicoMarch 14, 1979 · 24 km SW of this epicenter
- 7.525 km S of Tetitlán, MexicoDecember 16, 1911 · 129 km SE of this epicenter
- 7.527 km SSE of San Andrés Playa Encantada (El Podrido), MexicoJuly 30, 1909 · 242 km SE of this epicenter
- 7.535 km SW of Aguililla, MexicoJanuary 30, 1973 · 203 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 54 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 2,534 recorded deaths. The most severe:
- 1806M7.5
Jalisco,Oaxaca,Michoacan
25 Mar 1806 · 297 km away · intensity VIII
2,000 deathsExtreme damage ($25M+)
- 1912M6.7
Central, Acambay, Tixmadeje
19 Nov 1912 · 219 km away
202 deathsSevere damage ($5–24M)
- 1941M7.6
Michoacan, Colima, Jalisco
15 Apr 1941 · 209 km away · intensity VII
84 deaths$2 million damagetsunami
- 1964M7.3
Guerrero
6 Jul 1964 · 60 km away
78 deathsSevere damage ($5–24M)
- 1957M7.9
Acapulco,Mexico City
28 Jul 1957 · 274 km away · intensity VII
65 deaths$25 million damagetsunami
- 1973M7.5
S, Farias, Tecoman
30 Jan 1973 · 203 km away
56 deathsModerate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.