Reviewed by USGSGuam33y ago
M4.9 earthquake 70 km ESE of Yigo Village, Guam
Tuesday, September 7, 1993, 06:10:32 UTC · 13.298°N, 145.497°E
A magnitude 4.9 earthquake struck 70 km ESE of Yigo Village, Guam on Tuesday, September 7, 1993, 06:10:32 UTC, at a depth of 62.0 km (shallow). It is the strongest earthquake within 300 km since an M5.2 on September 4, 1993.
- Magnitude
- 4.9
- Light · mb
- Depth
- 62 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
338 tons of TNT
That is about 1/45 of the Hiroshima bomb. A magnitude 5.0 releases about 1 times more energy.
Tectonic setting
71 km
from the nearest mapped plate boundary, between the Mariana and Pacific plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
62 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 M5.2 on October 3, 1993. 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 347 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.832 km S of Inarajan Village, GuamAugust 8, 1993 · 83 km SW of this epicenter
- 7.2265 km S of Merizo Village, GuamJanuary 28, 1931 · 292 km SW of this epicenter
- 7.1261 km S of Merizo Village, GuamMay 9, 1917 · 290 km SW of this epicenter
- 7.0176 km ESE of San Jose Village, Northern Mariana IslandsMay 18, 1913 · 202 km NE of this epicenter
- 7.098 km SSE of Inarajan Village, GuamDecember 9, 1909 · 115 km SW of this epicenter
- 7.032 km NNE of Yigo Village, GuamOctober 26, 1912 · 83 km NW of this epicenter
- 7.0233 km ESE of Saipan, Northern Mariana IslandsJune 14, 1942 · 293 km NE of this epicenter
- 6.446 km ENE of Yigo Village, GuamOctober 29, 1936 · 56 km NW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 9 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1993M7.8
Tuman Bay, Apra Harbor
8 Aug 1993 · 83 km away · intensity IX
$250 million damagetsunami
- 1849M7.5
Guam
25 Jan 1849 · 250 km away · intensity IX
Severe damage ($5–24M)tsunami
- 1909M8.0
Guam
9 Dec 1909 · 104 km away · intensity VIII
Moderate damage ($1–5M)tsunami
- 1892M7.5
Guam
16 May 1892 · 250 km away · intensity VIII
Moderate damage ($1–5M)tsunami
- 1825
Ladrones Island
Apr 1825 · 250 km away · intensity VIII
Moderate damage ($1–5M)tsunami
- 1834
Agana
May 1834 · 250 km away
Moderate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.