4.5

M4.5 Earthquake 33 km NW of Ruteng, IndonesiaAugust 21, 2026

2026-08-21 16:05:28 UTC (1 hour ago) · approx. 12:05 AM UTC+8 local

Felt by 1 person across nearby locations. Aftershock of the M5.3 mainshock.

MagnitudeM4.5(mb)
Time16:05 UTC12:05 AM UTC+8
Depth10.0 kmshallow crustal
Coordinates-8.381°, 120.271°
Felt by1DYFI response
Status✓ Reviewed by USGS

On August 21, 2026 at 16:05 UTC, a magnitude 4.5 shallow crustal earthquake struck 33 km NW of Ruteng, Indonesia, at a depth of 10.0 km and coordinates -8.3813°, 120.2714°. This earthquake was detected by 16 seismic stations with good location accuracy and was assigned a USGS significance rating of 312, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.5 releases seismic energy equivalent to roughly 85 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 767 m — 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 5.3 mainshock that occurred 1 day ago 48 km NNE of Ruteng, Indonesia. Since the mainshock, the USGS has recorded 16 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

Map showing earthquake epicenter at -8.38°, 120.27°

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 1 citizen response to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.

USGS DYFI community-reported intensity map for the M4.5 earthquake near 33 km NW of Ruteng, Indonesia

Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report

Earthquake Details

Magnitude
4.5 mb
Depth
10.0 km
shallow crustal
Location
-8.3813°N
120.2714°E
Felt Reports
1
DYFI responses
Community Intensity
2.0
CDI from reports

Technical Information

Event ID
us6000tmkv
Event Type
earthquake
Status
✓ Reviewed
Significance
312
Stations Used
16
Azimuthal Gap
130.0°
Min Station Distance
3.385°
RMS Residual
0.79 sec
Last Updated
2026-08-21 17:07:16 UTC

Common Questions

How strong was the magnitude 4.5 earthquake near Ruteng, Indonesia?

The magnitude 4.5 earthquake that struck 33 km NW of Ruteng, Indonesia on August 21, 2026 at 16:05 UTC had a depth of 10.0 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at -8.3813°, 120.2714°, which is 33 km NW of Ruteng, Indonesia. View all earthquakes in Indonesia.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.5 earthquakes can continue for several days and gradually diminish over time.

Is this the same earthquake as the M5.3 one earlier?

No. This magnitude 4.5 earthquake is an aftershock of the larger magnitude 5.3 mainshock that occurred earlier 48 km NNE of Ruteng, 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 4.5 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us6000tmkv). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, August 21, 2026). M4.5 Earthquake 33 km NW of Ruteng, IndonesiaAugust 21, 2026. Retrieved August 21, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000tmkv/