4.8

M4.8 Earthquake 99 km SSE of Hengchun, TaiwanOctober 16, 2021

2021-10-16 15:35:02 UTC (2021-10-16) · approx. 11:35 PM UTC+8 local

MagnitudeM4.8(mb)
Time15:35 UTC11:35 PM UTC+8
Depth10.0 kmshallow crustal
Coordinates21.175°, 121.112°
Felt byNo felt reports
Status✓ Reviewed by USGS

On October 16, 2021 at 15:35 UTC, a magnitude 4.8 shallow crustal earthquake struck 99 km SSE of Hengchun, Taiwan, at a depth of 10.0 km and coordinates 21.1746°, 121.1120°.

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.

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 21.17°, 121.11°

Earthquake Details

Magnitude
4.8 mb
Depth
10.0 km
shallow crustal
Location
21.1746°N
121.1120°E

Technical Information

Event ID
us6000fv8w
Event Type
earthquake
Status
✓ Reviewed
Significance
354
Azimuthal Gap
57.0°
Min Station Distance
1.635°
RMS Residual
0.96 sec
Last Updated
2021-12-25 22:58:39 UTC

Common Questions

How strong was the magnitude 4.8 earthquake near Hengchun, Taiwan?

The magnitude 4.8 earthquake that struck 99 km SSE of Hengchun, Taiwan on October 16, 2021 at 15:35 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 21.1746°, 121.1120°, which is 99 km SSE of Hengchun, Taiwan. View all earthquakes in Taiwan.

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.

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 4.8 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us6000fv8w). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2021, October 16, 2021). M4.8 Earthquake 99 km SSE of Hengchun, TaiwanOctober 16, 2021. Retrieved December 25, 2021 from https://www.earthquaketracker.org/earthquakes/event/us6000fv8w/