5.9

M5.9 Earthquake in the Hokkaido, Japan regionAugust 11, 2023

2023-08-11 00:14:33 UTC (2023-08-11) · approx. 10:14 AM UTC+10 local

Felt by 5 people across nearby locations.

MagnitudeM5.9(mww)
Time00:14 UTC10:14 AM UTC+10
Depth34.0 kmshallow crustal
Coordinates41.122°, 142.830°
Felt by5DYFI responses· max MMI 3.7
Status✓ Reviewed by USGS· green PAGER
green Alertno significant casualties or damage expected

On August 11, 2023 at 00:14 UTC, a magnitude 5.9 shallow crustal earthquake struck in the Hokkaido, Japan region, at a depth of 34.0 km and coordinates 41.1218°, 142.8297°. The earthquake was reported felt by 5 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 3.7 (light). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. This earthquake was detected by 140 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 537, placing it among routine seismic activity. The nearest populated place is Mutsu (population 49,220).

Physical scale: An earthquake of magnitude 5.9 releases seismic energy equivalent to roughly 11 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 7.1 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

Mutsupop. 49,220
MMI 3.5 (light)
Uchimarupop. 0
MMI 3.5 (light)
Hachinohepop. 239,046
MMI 3.4 (light)
Furudatepop. 0
MMI 3.4 (light)
Inuotosepop. 0
MMI 3.4 (light)
Shizunai-furukawachopop. 22,436
MMI 3.4 (light)
Map showing earthquake epicenter at 41.12°, 142.83°

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 M5.9 earthquake near Hokkaido, Japan region

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

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 5 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 M5.9 earthquake near Hokkaido, Japan region

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 3weak3,058,765
MMI 4light114,867

Earthquake Details

Magnitude
5.9 mww
Depth
34.0 km
shallow crustal
Location
41.1218°N
142.8297°E
Felt Reports
5
DYFI responses
Intensity (MMI)
3.7
light
Community Intensity
3.4
CDI from reports

Technical Information

Event ID
us6000kz5s
Event Type
earthquake
Status
✓ Reviewed
Significance
537
Stations Used
140
Azimuthal Gap
71.0°
Min Station Distance
0.926°
RMS Residual
0.57 sec
Last Updated
2023-10-17 22:01:29 UTC

Common Questions

How strong was the magnitude 5.9 earthquake in the Hokkaido, Japan region?

The magnitude 5.9 earthquake that struck in the Hokkaido, Japan region on August 11, 2023 at 00:14 UTC had a depth of 34.0 km. It was felt by 5 people with maximum shaking intensity of MMI 3.7 (light). For context, this was a moderate earthquake that could be widely felt.

Where did the earthquake occur?

The earthquake epicenter was located at 41.1218°, 142.8297°, which is in the Hokkaido, Japan region. The nearest populated place is Mutsu (population 49,220). View all earthquakes in Japan.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.9 earthquakes can continue for days to weeks 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 5.9 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us6000kz5s). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, August 11, 2023). M5.9 Earthquake in the Hokkaido, Japan regionAugust 11, 2023. Retrieved October 17, 2023 from https://www.earthquaketracker.org/earthquakes/event/us6000kz5s/