Reviewed by USGS23y ago
M7.6 earthquake in Carlsberg Ridge
Tuesday, July 15, 2003, 20:27:50 UTC · 2.598°S, 68.382°E
A magnitude 7.6 earthquake struck in Carlsberg Ridge on Tuesday, July 15, 2003, 20:27:50 UTC, at a depth of 10.0 km (shallow). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.
- Magnitude
- 7.6
- Major · mwc
- Depth
- 10 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: 200 km aftershock search area
In context
How big was it, and why here?
Energy released
3.8 megatons of TNT
That is about 252 times the Hiroshima bomb. It released about 7,943 times the energy of a magnitude 5.0.
Tectonic setting
16 km
from the nearest mapped plate boundary, between the Indian and Somali plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
10 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 200 km
USGS lists 20 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M5.7 on July 28, 2003. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 5.7Carlsberg Ridge23y ago · 180 km NW of this epicenter
- 4.8Carlsberg Ridge23y ago · 178 km NE of this epicenter
- 4.6Carlsberg Ridge23y ago · 112 km NE of this epicenter
- 4.5Carlsberg Ridge23y ago · 49 km NE of this epicenter
- 4.6Carlsberg Ridge23y ago · 14 km NE of this epicenter
- 4.6Carlsberg Ridge23y ago · 65 km E of this epicenter
- 4.4Carlsberg Ridge23y ago · 53 km NE of this epicenter
- 4.9Carlsberg Ridge23y ago · 198 km NE of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 66 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 6.2Carlsberg RidgeSeptember 8, 1922 · 140 km SW of this epicenter
- 6.0Chagos Archipelago regionFebruary 22, 1956 · 118 km S of this epicenter
- 6.0Carlsberg RidgeSeptember 7, 1955 · 63 km NW of this epicenter
- 6.0Carlsberg RidgeJanuary 14, 1998 · 63 km NW of this epicenter
- 5.9Chagos Archipelago regionMarch 31, 1970 · 178 km SE of this epicenter
- 5.8Carlsberg RidgeMay 9, 1985 · 161 km NW of this epicenter
- 5.8Carlsberg RidgeAugust 9, 1959 · 170 km NW of this epicenter
- 5.7Carlsberg RidgeNovember 1, 1994 · 138 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 1 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 2003M7.6
Felt In Maldives
15 Jul 2003 · 0 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.