M4.8 Earthquake 200 km S of Pagar Alam, Indonesia — September 16, 2023
2023-09-16 01:29:19 UTC (2023-09-16) · approx. 8:29 AM UTC+7 local
Aftershock of the M5.2 mainshock.
On September 16, 2023 at 01:29 UTC, a magnitude 4.8 shallow crustal earthquake struck 200 km S of Pagar Alam, Indonesia, at a depth of 31.4 km and coordinates -5.8118°, 102.9512°. This earthquake was detected by 67 seismic stations with good location accuracy and was assigned a USGS significance rating of 354, placing it among routine seismic activity.
Physical scale: An earthquake of magnitude 4.8 releases seismic energy equivalent to roughly 239 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.2 km — a useful intuition for the size of the slip patch on the fault.
This earthquake is part of an ongoing aftershock sequence following the magnitude 5.2 mainshock that occurred 15 days ago 201 km SSW of Pagar Alam, Indonesia. Since the mainshock, the USGS has recorded 1 aftershocks in this area. Aftershock activity is expected to continue for days to weeks as stresses on surrounding faults redistribute.
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
Earthquake Details
102.9512°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.8 earthquake near Pagar Alam, Indonesia?
The magnitude 4.8 earthquake that struck 200 km S of Pagar Alam, Indonesia on September 16, 2023 at 01:29 UTC had a depth of 31.4 km. For context, this was a light earthquake commonly felt near the epicenter.
Where did the earthquake occur?
The earthquake epicenter was located at -5.8118°, 102.9512°, which is 200 km S of Pagar Alam, Indonesia. View all earthquakes in Indonesia.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.8 earthquakes can continue for several days and gradually diminish over time.
Is this the same earthquake as the M5.2 one earlier?
No. This magnitude 4.8 earthquake is an aftershock of the larger magnitude 5.2 mainshock that occurred earlier 201 km SSW of Pagar Alam, Indonesia. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.
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 4.8 event is significantly smaller than that historical record.
Authoritative source: USGS event page (event ID: us7000kw4e). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2023, September 16, 2023). M4.8 Earthquake 200 km S of Pagar Alam, Indonesia — September 16, 2023. Retrieved November 18, 2023 from https://www.earthquaketracker.org/earthquakes/event/us7000kw4e/