Reviewed by USGSIndonesia47y ago
M6.9 earthquake south of Java, Indonesia
Tuesday, July 24, 1979, 19:31:19 UTC · 11.149°S, 107.709°E
A magnitude 6.9 earthquake struck south of Java, Indonesia on Tuesday, July 24, 1979, 19:31:19 UTC, at a depth of 31.0 km (shallow). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.
- Magnitude
- 6.9
- Strong · ms
- Depth
- 31 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: 100 km aftershock search area
In context
How big was it, and why here?
Energy released
338 kilotons of TNT
That is about 22 times the Hiroshima bomb. It released about 708 times the energy of a magnitude 5.0.
Tectonic setting
121 km
from the nearest mapped plate boundary, between the Sunda and Australian plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
31 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 100 km
USGS lists 1 M2.5+ earthquake within 100 km in the following 30 days; the largest was M4.3 on July 31, 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 17 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 6.5260 km SSW of Kroya, IndonesiaSeptember 7, 1974 · 164 km NE of this epicenter
- 6.5south of Java, IndonesiaDecember 12, 1924 · 294 km E of this epicenter
- 6.3136 km S of Kawalu, IndonesiaSeptember 14, 1944 · 285 km N of this epicenter
- 6.3south of Java, IndonesiaMarch 21, 1940 · 103 km N of this epicenter
- 6.2187 km S of Banjar, IndonesiaMay 12, 1957 · 254 km N of this epicenter
- 6.0190 km S of Banjar, IndonesiaFebruary 11, 1958 · 251 km N of this epicenter
- 6.0270 km S of Kawalu, IndonesiaMay 10, 1940 · 151 km N of this epicenter
- 6.0183 km S of Banjar, IndonesiaApril 29, 1957 · 265 km N of this epicenter