3.0

M3.0 Earthquake 4 km S of P?hala, HawaiiOctober 16, 2021

2021-10-16 23:35:52 UTC (2021-10-16) · approx. 1:35 PM UTC-10 local

MagnitudeM3.0(ml)
Time23:35 UTC1:35 PM UTC-10
Depth33.1 kmshallow crustal
Coordinates19.160°, -155.470°
Felt by3DYFI responses
Status✓ Reviewed by USGS

On October 16, 2021 at 23:35 UTC, a magnitude 3.0 shallow crustal earthquake struck 4 km S of P?hala, Hawaii, at a depth of 33.1 km and coordinates 19.1600°, -155.4697°.

Physical scale: An earthquake of magnitude 3.0 releases seismic energy equivalent to roughly 461 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 70 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 19.16°, -155.47°

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 3 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 M3.0 earthquake near 4 km S of P?hala, Hawaii

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

Earthquake Details

Magnitude
3.0 ml
Depth
33.1 km
shallow crustal
Location
19.1600°N
-155.4697°E
Felt Reports
3
DYFI responses
Community Intensity
2.0
CDI from reports

Technical Information

Event ID
hv72759117
Event Type
earthquake
Status
✓ Reviewed
Significance
138
Stations Used
54
Azimuthal Gap
105.0°
RMS Residual
0.11 sec
Last Updated
2022-08-08 10:34:36 UTC

Common Questions

How strong was the magnitude 3.0 earthquake near P?hala, Hawaii?

The magnitude 3.0 earthquake that struck 4 km S of P?hala, Hawaii on October 16, 2021 at 23:35 UTC had a depth of 33.1 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 3.0 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 3.0 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: hv72759117). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2021, October 16, 2021). M3.0 Earthquake 4 km S of P?hala, HawaiiOctober 16, 2021. Retrieved August 8, 2022 from https://www.earthquaketracker.org/earthquakes/event/hv72759117/