QuakeScout
Magnitude4.5

Reviewed by USGSIndonesia52y ago

M4.5 earthquake 260 km SSW of Sidareja, Indonesia

Saturday, September 21, 1974, 06:36:25 UTC · 9.764°S, 108.182°E

A magnitude 4.5 earthquake struck 260 km SSW of Sidareja, Indonesia on Saturday, September 21, 1974, 06:36:25 UTC, at a depth of 49.0 km (shallow). It is the strongest earthquake within 300 km since an M5.5 on September 18, 1974.

Magnitude
4.5
Light · mb
Depth
49 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

85 tons of TNT

That is about 1/178 of the Hiroshima bomb. A magnitude 5.0 releases about 6 times more energy.

Tectonic setting

40 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

49 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 38 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

  1. 7.6233 km S of Pundong, IndonesiaSeptember 11, 1921 · 272 km E of this epicenter
  2. 7.487 km SSW of Srandakan, IndonesiaJuly 23, 1943 · 222 km NE of this epicenter
  3. 7.1138 km SSE of Pundong, IndonesiaSeptember 10, 1926 · 277 km E of this epicenter
  4. 6.992 km S of Pundong, IndonesiaSeptember 27, 1937 · 269 km NE of this epicenter
  5. 6.5260 km SSW of Kroya, IndonesiaSeptember 7, 1974 · 20 km E of this epicenter
  6. 6.3136 km S of Kawalu, IndonesiaSeptember 14, 1944 · 129 km N of this epicenter
  7. 6.3south of Java, IndonesiaMarch 21, 1940 · 72 km SW of this epicenter
  8. 6.2166 km SSW of Bambanglipuro, IndonesiaAugust 31, 1918 · 190 km E of this epicenter

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 6 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 214 recorded deaths. The most severe:

  1. 1943M8.1

    Java: Jogyakarta

    23 Jul 1943 · 201 km away · intensity VIII

    213 deathsSevere damage ($5–24M)

  2. 1937M7.2

    Java: Jogyakarta: Klumpit,Prambanan

    27 Sep 1937 · 225 km away · intensity IX

    1 deathSevere damage ($5–24M)

  3. 1863

    Java: Banyumas

    31 Jul 1863 · 280 km away

    Moderate damage ($1–5M)

  4. 1923

    Java: Maos

    15 May 1923 · 255 km away · intensity IX

    Moderate damage ($1–5M)

  5. 1904

    S. Java

    7 Sep 1904 · 246 km away

    tsunami

  6. 1957

    S. Java Sea

    26 Sep 1957 · 199 km away

    tsunami

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

Nearby trackers

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