M5.5 Earthquake 109 km NNE of Bangkalan, Indonesia — August 4, 2023
2023-08-04 00:31:44 UTC (2023-08-04) · approx. 8:31 AM UTC+8 local
On August 4, 2023 at 00:31 UTC, a magnitude 5.5 deep-focus earthquake struck 109 km NNE of Bangkalan, Indonesia, at a depth of 575.7 km and coordinates -6.1265°, 113.0930°. The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. This earthquake was detected by 122 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 465, placing it among routine seismic activity. The nearest populated place is Wulung (population 0).
Physical scale: An earthquake of magnitude 5.5 releases seismic energy equivalent to roughly 3 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 3.8 km — a useful intuition for the size of the slip patch on the fault.
The epicenter is located in Indonesia, a region characterized by the convergence of the Indo-Australian, Eurasian, and Philippine Sea plates, forming the Sunda-Banda arc system. The nearest mapped fault system is the Sunda megathrust. View all earthquakes in Indonesia.
Learn more: Magnitude scale · Aftershock sequences
Nearest Populated Places
ShakeMap — predicted shaking intensity
Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.
Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS
Earthquake Details
113.0930°E
Technical Information
Common Questions
How strong was the magnitude 5.5 earthquake near Bangkalan, Indonesia?
The magnitude 5.5 earthquake that struck 109 km NNE of Bangkalan, Indonesia on August 4, 2023 at 00:31 UTC had a depth of 575.7 km. For context, this was a moderate earthquake that could be widely felt.
Where did the earthquake occur?
The earthquake epicenter was located at -6.1265°, 113.0930°, which is 109 km NNE of Bangkalan, Indonesia. The nearest populated place is Wulung (population 0). View all earthquakes in Indonesia.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.5 earthquakes can continue for days to weeks and gradually diminish over time.
Has Indonesia had earthquakes this big before?
The largest recorded earthquake in Indonesia was the M9.1 Indian Ocean earthquake of December 26, 2004. Today's magnitude 5.5 event is significantly smaller than that historical record.
Authoritative source: USGS event page (event ID: us6000kxp7). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2023, August 4, 2023). M5.5 Earthquake 109 km NNE of Bangkalan, Indonesia — August 4, 2023. Retrieved October 7, 2023 from https://www.earthquaketracker.org/earthquakes/event/us6000kxp7/