4.6

M4.6 Earthquake 159 km NW of Tobelo, Indonesia — January 18, 2023

2023-01-18 20:57:50 UTC (2023-01-18) · approx. 4:57 AM UTC+8 local

Aftershock of the M5.3 mainshock.

MagnitudeM4.6(mb)
Time20:57 UTC≈ 4:57 AM UTC+8
Depth46.4 kmshallow crustal
Coordinates2.744°, 126.997°
Felt byNo felt reports
Status✓ Reviewed by USGS

On January 18, 2023 at 20:57 UTC, a magnitude 4.6 shallow crustal earthquake struck 159 km NW of Tobelo, Indonesia, at a depth of 46.4 km and coordinates 2.7438°, 126.9974°. This earthquake was detected by 57 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 326, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.6 releases seismic energy equivalent to roughly 120 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 899 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 17 days ago 161 km WNW of Tobelo, 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

Map showing earthquake epicenter at 2.74°, 127.00°

Earthquake Details

Magnitude
4.6 mb
Depth
46.4 km
shallow crustal
Location
2.7438°N
126.9974°E

Technical Information

Event ID
us7000j5c1
Event Type
earthquake
Status
✓ Reviewed
Significance
326
Stations Used
57
Azimuthal Gap
84.0°
Min Station Distance
1.993°
RMS Residual
0.79 sec
Last Updated
2024-01-18 19:13:08 UTC

Common Questions

How strong was the magnitude 4.6 earthquake near Tobelo, Indonesia?

The magnitude 4.6 earthquake that struck 159 km NW of Tobelo, Indonesia on January 18, 2023 at 20:57 UTC had a depth of 46.4 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 2.7438°, 126.9974°, which is 159 km NW of Tobelo, Indonesia. View all earthquakes in Indonesia.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.6 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 4.6 earthquake is an aftershock of the larger magnitude 5.3 mainshock that occurred earlier 161 km WNW of Tobelo, 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 4.6 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us7000j5c1). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, January 18, 2023). M4.6 Earthquake 159 km NW of Tobelo, Indonesia — January 18, 2023. Retrieved January 18, 2024 from https://www.earthquaketracker.org/earthquakes/event/us7000j5c1/