6.3

M6.3 Earthquake 18 km W of Uwajima, JapanApril 17, 2024

2024-04-17 14:14:46 UTC (2024-04-17) · approx. 11:14 PM UTC+9 local

Felt by 101 people across surrounding communities. Maximum shaking intensity MMI 8.2 (violent).

MagnitudeM6.3(mww)
Time14:14 UTC11:14 PM UTC+9
Depth32.0 kmshallow crustal
Coordinates33.250°, 132.365°
Felt by101DYFI responses· max MMI 8.2
Status✓ Reviewed by USGS· yellow PAGER
yellow Alertlocal impact possible

On April 17, 2024 at 14:14 UTC, a magnitude 6.3 shallow crustal earthquake struck 18 km W of Uwajima, Japan, at a depth of 32.0 km and coordinates 33.2503°, 132.3647°. The earthquake was reported felt by 101 peopleacross surrounding communities, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 8.2 (violent). The USGS PAGER system issued a yellow alert level for this event, indicating local impact possible. This earthquake was detected by 386 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 731, making it a moderate-impact event. The nearest populated place is Uwajima (population 58,971).

Physical scale: An earthquake of magnitude 6.3 releases seismic energy equivalent to roughly 43 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 13 km — a useful intuition for the size of the slip patch on the fault.

The epicenter is located in Japan, a region characterized by the intersection of four tectonic plates — Pacific, Philippine Sea, Eurasian, and North American — creating multiple subduction zones. The nearest mapped fault system is the Japan Trench. View all earthquakes in Japan.

Learn more: Magnitude scale · Aftershock sequences

Nearest Populated Places

Uwajimapop. 58,971
MMI 8.0 (severe)
Sukumopop. 25,784
MMI 7.2 (severe)
Nakamurapop. 34,559
MMI 6.4 (very strong)
Kihoku-chopop. 11,712
MMI 6.4 (very strong)
Saikipop. 49,065
MMI 6.2 (very strong)
Masaki-chopop. 30,548
MMI 5.6 (strong)

What the Shaking Felt Like

At MMI 8.2 (violent), people in the most strongly affected areas would have experienced: Severe shaking causing considerable damage. Buildings may shift off foundations. Walls crack and may partially collapse. Heavy furniture overturned.

Map showing earthquake epicenter at 33.25°, 132.36°

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 M6.3 earthquake near 18 km W of Uwajima, Japan

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

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 101 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 M6.3 earthquake near 18 km W of Uwajima, Japan

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 3weak8,874,036
MMI 4light9,701,992
MMI 5moderate1,455,820
MMI 6strong257,026
MMI 7very strong69,684
MMI 8severe20,831

Earthquake Details

Magnitude
6.3 mww
Depth
32.0 km
shallow crustal
Location
33.2503°N
132.3647°E
Felt Reports
101
DYFI responses
Intensity (MMI)
8.2
violent
Community Intensity
8.0
CDI from reports

Technical Information

Event ID
us7000mcpi
Event Type
earthquake
Status
✓ Reviewed
Significance
731
Stations Used
386
Azimuthal Gap
29.0°
Min Station Distance
1.351°
RMS Residual
0.81 sec
Last Updated
2025-09-08 03:45:15 UTC

Common Questions

How strong was the magnitude 6.3 earthquake near Uwajima, Japan?

The magnitude 6.3 earthquake that struck 18 km W of Uwajima, Japan on April 17, 2024 at 14:14 UTC had a depth of 32.0 km. It was felt by 101 people with maximum shaking intensity of MMI 8.2 (violent). For context, this was a strong earthquake capable of causing significant damage.

Where did the earthquake occur?

The earthquake epicenter was located at 33.2503°, 132.3647°, which is 18 km W of Uwajima, Japan. The nearest populated place is Uwajima (population 58,971). View all earthquakes in Japan.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 6.3 earthquakes can continue for weeks to months and gradually diminish over time.

Has Japan had earthquakes this big before?

The largest recorded earthquake in Japan was the M9.1 Tohoku earthquake of March 11, 2011. Today's magnitude 6.3 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us7000mcpi). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2024, April 17, 2024). M6.3 Earthquake 18 km W of Uwajima, JapanApril 17, 2024. Retrieved September 8, 2025 from https://www.earthquaketracker.org/earthquakes/event/us7000mcpi/