4.9

M4.9 Earthquake 91 km WSW of Hengchun, Taiwan — January 25, 2021

2021-01-25 14:24:44 UTC (2021-01-25) · approx. 10:24 PM UTC+8 local

Felt by 1 person across nearby locations.

MagnitudeM4.9(mb)
Time14:24 UTC≈ 10:24 PM UTC+8
Depth10.0 kmshallow crustal
Coordinates21.776°, 119.893°
Felt by1DYFI response
Status✓ Reviewed by USGS

On January 25, 2021 at 14:24 UTC, a magnitude 4.9 shallow crustal earthquake struck 91 km WSW of Hengchun, Taiwan, at a depth of 10.0 km and coordinates 21.7756°, 119.8932°.

Physical scale: An earthquake of magnitude 4.9 releases seismic energy equivalent to roughly 338 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.4 km — a useful intuition for the size of the slip patch on the fault.

The epicenter is located in Taiwan, a region characterized by the collision of the Luzon volcanic arc with the Eurasian continental margin, where the Philippine Sea Plate converges at 80 mm per year. View all earthquakes in Taiwan.

Learn more: Magnitude scale · Aftershock sequences

Map showing earthquake epicenter at 21.78°, 119.89°

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 M4.9 earthquake near 91 km WSW of Hengchun, Taiwan

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

Earthquake Details

Magnitude
4.9 mb
Depth
10.0 km
shallow crustal
Location
21.7756°N
119.8932°E
Felt Reports
1
DYFI responses
Community Intensity
1.0
CDI from reports

Technical Information

Event ID
us7000d34w
Event Type
earthquake
Status
✓ Reviewed
Significance
369
Azimuthal Gap
100.0°
Min Station Distance
1.511°
RMS Residual
0.64 sec
Last Updated
2022-08-09 02:39:02 UTC

Common Questions

How strong was the magnitude 4.9 earthquake near Hengchun, Taiwan?

The magnitude 4.9 earthquake that struck 91 km WSW of Hengchun, Taiwan on January 25, 2021 at 14:24 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 21.7756°, 119.8932°, which is 91 km WSW of Hengchun, Taiwan. View all earthquakes in Taiwan.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.9 earthquakes can continue for several days and gradually diminish over time.

Has Taiwan had earthquakes this big before?

The largest recorded earthquake in Taiwan was the M7.6 Chi-Chi earthquake of September 21, 1999. Today's magnitude 4.9 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us7000d34w). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2021, January 25, 2021). M4.9 Earthquake 91 km WSW of Hengchun, Taiwan — January 25, 2021. Retrieved August 9, 2022 from https://www.earthquaketracker.org/earthquakes/event/us7000d34w/