M6.4 Earthquake 148 km WSW of Buala, Solomon Islands — October 15, 2021
2021-10-15 02:44:59 UTC (2021-10-15) · approx. 1:44 PM UTC+11 local
Felt by 23 people across nearby locations. Maximum shaking intensity MMI 6.3 (very strong).
On October 15, 2021 at 02:44 UTC, a magnitude 6.4 shallow crustal earthquake struck 148 km WSW of Buala, Solomon Islands, at a depth of 33.0 km and coordinates -8.8783°, 158.4642°. The earthquake was reported felt by 23 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 6.3 (very strong). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. The nearest populated place is Tulaghi (population 1,750).
Physical scale: An earthquake of magnitude 6.4 releases seismic energy equivalent to roughly 60 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 16 km — a useful intuition for the size of the slip patch on the fault.
Nearest Populated Places
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 23 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 | 152,289 |
| MMI 4 | light | 354,100 |
| MMI 5 | moderate | 17,217 |
| MMI 6 | strong | 5,841 |
Earthquake Details
158.4642°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 6.4 earthquake near Buala, Solomon Islands?
The magnitude 6.4 earthquake that struck 148 km WSW of Buala, Solomon Islands on October 15, 2021 at 02:44 UTC had a depth of 33.0 km. It was felt by 23 people with maximum shaking intensity of MMI 6.3 (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 -8.8783°, 158.4642°, which is 148 km WSW of Buala, Solomon Islands. The nearest populated place is Tulaghi (population 1,750).
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 6.4 earthquakes can continue for weeks to months and gradually diminish over time.
Authoritative source: USGS event page (event ID: us6000furk). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, October 15, 2021). M6.4 Earthquake 148 km WSW of Buala, Solomon Islands — October 15, 2021. Retrieved December 22, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000furk/