M6.2 Earthquake 27 km SSE of Naalehu, Hawaii — October 10, 2021
2021-10-10 21:48:36 UTC (2021-10-10) · approx. 11:48 AM UTC-10 local
Felt by 3,487 people across a wide area. Maximum shaking intensity MMI 6.7 (very strong).
On October 10, 2021 at 21:48 UTC, a magnitude 6.2 shallow crustal earthquake struck 27 km SSE of Naalehu, Hawaii, at a depth of 35.1 km and coordinates 18.8203°, -155.5272°. The earthquake was reported felt by 3,487 peopleacross a wide area, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 6.7 (very strong). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. This earthquake was detected by 54 seismic stations with limited location accuracy due to sparse station coverage and was assigned a USGS significance rating of 1173, making it one of the most significant global earthquakes in recent days. The nearest populated place is Hawaiian Ocean View (population 4,437).
Physical scale: An earthquake of magnitude 6.2 releases seismic energy equivalent to roughly 31 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 12 km — a useful intuition for the size of the slip patch on the fault.
The epicenter is located in Hawaii, a region characterized by intraplate volcanic activity over the Hawaiian mantle plume hotspot, with seismicity driven by magma intrusion and flank instability. View all earthquakes in Hawaii.
Learn more: Magnitude scale · Aftershock sequences
Nearest Populated Places
What the Shaking Felt Like
At MMI 6.7 (very strong), people in the most strongly affected areas would have experienced: Strong shaking felt by everyone. Heavy furniture may move. Books fall from shelves. Plaster and chimneys may crack. Damage is generally slight in well-built structures.
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.
Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 3,487 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.
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) | Description | Population exposed |
|---|---|---|
| MMI 3 | weak | 19,128 |
| MMI 4 | light | 170,387 |
| MMI 5 | moderate | 18,540 |
| MMI 6 | strong | 2,950 |
Earthquake Details
-155.5272°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 6.2 earthquake near Naalehu, Hawaii?
The magnitude 6.2 earthquake that struck 27 km SSE of Naalehu, Hawaii on October 10, 2021 at 21:48 UTC had a depth of 35.1 km. It was felt by 3,487 people with maximum shaking intensity of MMI 6.7 (very strong). For context, this was a strong earthquake capable of causing significant damage.
Where did the earthquake occur?
The earthquake epicenter was located at 18.8203°, -155.5272°, which is 27 km SSE of Naalehu, Hawaii. The nearest populated place is Hawaiian Ocean View (population 4,437). View all earthquakes in Hawaii.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 6.2 earthquakes can continue for weeks to months and gradually diminish over time.
Has Hawaii had earthquakes this big before?
The largest recorded earthquake in Hawaii was the M7.9 Ka'u District earthquake of April 2, 1868. Today's magnitude 6.2 event is significantly smaller than that historical record.
Authoritative source: USGS event page (event ID: hv72748782). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, October 10, 2021). M6.2 Earthquake 27 km SSE of Naalehu, Hawaii — October 10, 2021. Retrieved December 22, 2025 from https://www.earthquaketracker.org/earthquakes/event/hv72748782/