5.8

M5.8 Earthquake 15 km SSW of Hualien City, Taiwan — April 18, 2021

2021-04-18 14:14:36 UTC (2021-04-18) · approx. 10:14 PM UTC+8 local

Felt by 69 people across nearby locations. Maximum shaking intensity MMI 7.5 (severe).

MagnitudeM5.8(mww)
Time14:14 UTC≈ 10:14 PM UTC+8
Depth12.0 kmshallow crustal
Coordinates23.857°, 121.526°
Felt by69DYFI responses· max MMI 7.5
Status✓ Reviewed by USGS· green PAGER
green Alert— no significant casualties or damage expected

On April 18, 2021 at 14:14 UTC, a magnitude 5.8 shallow crustal earthquake struck 15 km SSW of Hualien City, Taiwan, at a depth of 12.0 km and coordinates 23.8570°, 121.5264°. The earthquake was reported felt by 69 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 7.5 (severe). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. The nearest populated place is Hualien City (population 350,468).

Physical scale: An earthquake of magnitude 5.8 releases seismic energy equivalent to roughly 8 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 6.1 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

Nearest Populated Places

Hualien Citypop. 350,468
MMI 5.9 (strong)
Douliupop. 104,723
MMI 4.5 (moderate)
Hsinchupop. 404,109
MMI 4.4 (moderate)
Pulipop. 86,406
MMI 4.3 (moderate)
Chang-huapop. 0
MMI 4.2 (moderate)
Zhubeipop. 0
MMI 4.2 (moderate)
Map showing earthquake epicenter at 23.86°, 121.53°

ShakeMap — predicted shaking intensity

Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.

USGS ShakeMap intensity contours for the M5.8 earthquake near 15 km SSW of Hualien City, Taiwan

Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 69 citizen responses 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 M5.8 earthquake near 15 km SSW of Hualien City, Taiwan

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

Population exposure (USGS PAGER)

Estimated population that experienced each level of shaking. Based on the USGS PAGER rapid impact assessment, which combines ShakeMap output with global population grids.

Shaking intensity (MMI)DescriptionPopulation exposed
MMI 3weak8,358,445
MMI 4light15,773,192
MMI 5moderate86,051
MMI 6strong186,761
MMI 7very strong27,191
MMI 8severe195

Earthquake Details

Magnitude
5.8 mww
Depth
12.0 km
shallow crustal
Location
23.8570°N
121.5264°E
Felt Reports
69
DYFI responses
Intensity (MMI)
7.5
severe
Community Intensity
9.1
CDI from reports

Technical Information

Event ID
us6000e2mv
Event Type
earthquake
Status
✓ Reviewed
Significance
580
Azimuthal Gap
24.0°
Min Station Distance
0.321°
RMS Residual
0.69 sec
Last Updated
2025-12-22 19:07:02 UTC

Common Questions

How strong was the magnitude 5.8 earthquake near Hualien City, Taiwan?

The magnitude 5.8 earthquake that struck 15 km SSW of Hualien City, Taiwan on April 18, 2021 at 14:14 UTC had a depth of 12.0 km. It was felt by 69 people with maximum shaking intensity of MMI 7.5 (severe). For context, this was a moderate earthquake that could be widely felt.

Where did the earthquake occur?

The earthquake epicenter was located at 23.8570°, 121.5264°, which is 15 km SSW of Hualien City, Taiwan. The nearest populated place is Hualien City (population 350,468). View all earthquakes in Taiwan.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.8 earthquakes can continue for days to weeks 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 5.8 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us6000e2mv). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2021, April 18, 2021). M5.8 Earthquake 15 km SSW of Hualien City, Taiwan — April 18, 2021. Retrieved December 22, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000e2mv/