4.9

M4.9 Earthquake 33 km NE of Shinshiro, Japan — September 27, 2020

2020-09-27 04:13:41 UTC (2020-09-27) · approx. 1:13 PM UTC+9 local

Felt by 23 people across nearby locations.

MagnitudeM4.9(mww)
Time04:13 UTC≈ 1:13 PM UTC+9
Depth45.1 kmshallow crustal
Coordinates35.108°, 137.768°
Felt by23DYFI responses
Status✓ Reviewed by USGS

On September 27, 2020 at 04:13 UTC, a magnitude 4.9 shallow crustal earthquake struck 33 km NE of Shinshiro, Japan, at a depth of 45.1 km and coordinates 35.1077°, 137.7678°.

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 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

Map showing earthquake epicenter at 35.11°, 137.77°

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 23 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 M4.9 earthquake near 33 km NE of Shinshiro, Japan

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

Earthquake Details

Magnitude
4.9 mww
Depth
45.1 km
shallow crustal
Location
35.1077°N
137.7678°E
Felt Reports
23
DYFI responses
Community Intensity
4.1
CDI from reports

Technical Information

Event ID
us6000c1tl
Event Type
earthquake
Status
✓ Reviewed
Significance
379
Azimuthal Gap
55.0°
Min Station Distance
0.548°
RMS Residual
1.08 sec
Last Updated
2025-12-22 18:42:56 UTC

Common Questions

How strong was the magnitude 4.9 earthquake near Shinshiro, Japan?

The magnitude 4.9 earthquake that struck 33 km NE of Shinshiro, Japan on September 27, 2020 at 04:13 UTC had a depth of 45.1 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 35.1077°, 137.7678°, which is 33 km NE of Shinshiro, Japan. View all earthquakes in Japan.

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 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 4.9 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us6000c1tl). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2020, September 27, 2020). M4.9 Earthquake 33 km NE of Shinshiro, Japan — September 27, 2020. Retrieved December 22, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000c1tl/