M7.7 earthquake 226 km SSW of Singaparna, Indonesia

Monday, July 17, 2006, 08:19:26 UTC · 9.284°S, 107.419°E

A magnitude 7.7 earthquake struck 226 km SSW of Singaparna, Indonesia on Monday, July 17, 2006, 08:19:26 UTC, at a depth of 20.0 km (shallow). USGS received 48 “Did You Feel It?” reports, with a maximum reported intensity of VII (very strong). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.

Magnitude: 7.7; Major · mwc
Depth: 20 km; Shallow
Felt reports: 48; Max intensity VII
Est. shaking: V; Moderate (ShakeMap)
PAGER alert: None; Not issued
Tsunami: No flag; USGS feed

Outlined circle: this earthquakeDashed circle: 200 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

5.4 megatons of TNT

That is about 355 times the Hiroshima bomb. It released about 11,220 times the energy of a magnitude 5.0.

Tectonic setting

64 km

from the nearest mapped plate boundary, between the Sunda and Australian plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.

Depth: shallow

20 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

Reports sent by people to USGS, grouped by place (most reports first). Intensity uses the Modified Mercalli scale (I–X): what people felt, not the magnitude.

Place	Intensity	Reports	Distance
Jakarta, Jakarta, Indonesia	IV · Light	28	349 km
Yogyakarta, Yogyakarta, Indonesia	VII · Very strong	2	365 km
Kuala Lumpur, Kuala Lumpur, Malaysia	III · Weak	2	1515 km
Singapore, _no region, Singapore	II · Weak	2	1235 km
Bandung, Jawa Barat, Indonesia	II · Weak	2	264 km
Medan, Sumatera Utara, Indonesia	VI · Strong	1	1724 km
Bogor, Jawa Barat, Indonesia	IV · Light	1	307 km
Cilacap, Jawa Tengah, Indonesia	III · Weak	1	277 km
Kuningan, Jawa Barat, Indonesia	III · Weak	1	281 km
Broome, Western Australia, Australia	III · Weak	1	1868 km
Depok, Jawa Barat, Indonesia	II · Weak	1	327 km
Banda Aceh, Aceh, Indonesia	II · Weak	1	2121 km

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 375 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M6.1 on July 17, 2006. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 198 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 21 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 1,055 recorded deaths. The most severe:

2006M7.7
Java
17 Jul 2006 · 0 km away
802 deaths$55 million damagetsunami
1943M8.1
Java: Jogyakarta
23 Jul 1943 · 284 km away · intensity VIII
213 deathsSevere damage ($5–24M)
1979M6.1
Java
2 Nov 1979 · 203 km away
30 deaths$16 million damage
1875
W Java: Kuningan
25 Oct 1875 · 282 km away · intensity VIII
7 deathsSevere damage ($5–24M)
1971M5.2
Java: Buaran,Bantar Kawsun,Jipang
16 Jun 1971 · 297 km away
1 deathSevere damage ($5–24M)
1975M5.6
Java
9 Feb 1975 · 298 km away · intensity VIII
1 deathModerate damage ($1–5M)

NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.

Nearby trackers