Reviewed by USGSGuam24y ago
M4.0 earthquake 207 km SW of Merizo Village, Guam
Thursday, May 23, 2002, 17:27:29 UTC · 11.788°N, 143.488°E
A magnitude 4.0 earthquake struck 207 km SW of Merizo Village, Guam on Thursday, May 23, 2002, 17:27:29 UTC, at a depth of 33.0 km (shallow).
- Magnitude
- 4.0
- 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 earthquake
In context
How big was it, and why here?
Energy released
15 tons of TNT
That is about 1/998 of the Hiroshima bomb. A magnitude 5.0 releases about 32 times more energy.
Tectonic setting
30 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
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 has not published any M2.5+ earthquake within 50 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 471 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 · 195 km NE of this epicenter
- 7.2265 km S of Merizo Village, GuamJanuary 28, 1931 · 147 km SE of this epicenter
- 7.1261 km S of Merizo Village, GuamMay 9, 1917 · 140 km SE of this epicenter
- 7.120 km SSW of Merizo Village, GuamApril 26, 2002 · 190 km NE of this epicenter
- 7.098 km SSE of Inarajan Village, GuamDecember 9, 1909 · 173 km NE of this epicenter
- 7.032 km NNE of Yigo Village, GuamOctober 26, 1912 · 276 km NE of this epicenter
- 7.069 km SSE of Inarajan Village, GuamOctober 12, 2001 · 190 km NE of this epicenter
- 6.7Mariana Islands regionOctober 18, 1935 · 238 km W of this epicenter
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. The most severe:
- 1993M7.8
Tuman Bay, Apra Harbor
8 Aug 1993 · 195 km away · intensity IX
$250 million damagetsunami
- 1849M7.5
Guam
25 Jan 1849 · 247 km away · intensity IX
Severe damage ($5–24M)tsunami
- 1909M8.0
Guam
9 Dec 1909 · 182 km away · intensity VIII
Moderate damage ($1–5M)tsunami
- 1892M7.5
Guam
16 May 1892 · 247 km away · intensity VIII
Moderate damage ($1–5M)tsunami
- 2001M7.0
Guam
12 Oct 2001 · 190 km away · intensity VIII
Moderate damage ($1–5M)
- 1825
Ladrones Island
Apr 1825 · 247 km away · intensity VIII
Moderate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.