2.4

M2.4 Earthquake 24 km SE of Waimea, HawaiiSeptember 23, 2021

2021-09-23 22:51:39 UTC (2021-09-23) · approx. 12:51 PM UTC-10 local

MagnitudeM2.4(md)
Time22:51 UTC12:51 PM UTC-10
Depth24.6 kmshallow crustal
Coordinates19.845°, -155.528°
Felt by1DYFI response
Status✓ Reviewed by USGS

On September 23, 2021 at 22:51 UTC, a magnitude 2.4 shallow crustal earthquake struck 24 km SE of Waimea, Hawaii, at a depth of 24.6 km and coordinates 19.8450°, -155.5283°.

Physical scale: An earthquake of magnitude 2.4 releases seismic energy equivalent to roughly 66.6 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 29 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 19.84°, -155.53°

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 1 citizen response 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 M2.4 earthquake near 24 km SE of Waimea, Hawaii

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

Earthquake Details

Magnitude
2.4 md
Depth
24.6 km
shallow crustal
Location
19.8450°N
-155.5283°E
Felt Reports
1
DYFI responses
Community Intensity
2.0
CDI from reports

Technical Information

Event ID
hv72721972
Event Type
earthquake
Status
✓ Reviewed
Significance
91
Stations Used
46
Azimuthal Gap
101.0°
RMS Residual
0.13 sec
Last Updated
2021-09-24 01:21:51 UTC

Common Questions

How strong was the magnitude 2.4 earthquake near Waimea, Hawaii?

The magnitude 2.4 earthquake that struck 24 km SE of Waimea, Hawaii on September 23, 2021 at 22:51 UTC had a depth of 24.6 km. For context, this was a minor earthquake typically detected only by instruments.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 2.4 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 2.4 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: hv72721972). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2021, September 23, 2021). M2.4 Earthquake 24 km SE of Waimea, HawaiiSeptember 23, 2021. Retrieved September 24, 2021 from https://www.earthquaketracker.org/earthquakes/event/hv72721972/