M7.1 Earthquake southeast of the Loyalty Islands — May 20, 2023
2023-05-20 01:50:59 UTC (2023-05-20) · approx. 12:50 PM UTC+11 local
Felt by 6 people across nearby locations. 0
On May 20, 2023 at 01:50 UTC, a magnitude 7.1 shallow crustal earthquake struck southeast of the Loyalty Islands, at a depth of 27.3 km and coordinates -23.0421°, 170.5603°.0 The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. This earthquake was detected by 235 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 777, making it a moderate-impact event.
Physical scale: An earthquake of magnitude 7.1 releases seismic energy equivalent to roughly 674 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 48 km — a useful intuition for the size of the slip patch on the fault.
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 6 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 5 | moderate | 6 |
Earthquake Details
170.5603°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 7.1 earthquake southeast of the Loyalty Islands?
The magnitude 7.1 earthquake that struck southeast of the Loyalty Islands on May 20, 2023 at 01:50 UTC had a depth of 27.3 km. For context, this was a strong earthquake capable of causing significant damage.
Where did the earthquake occur?
The earthquake epicenter was located at -23.0421°, 170.5603°, which is southeast of the Loyalty Islands.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 7.1 earthquakes can continue for months to years and gradually diminish over time.
Actions
Authoritative source: USGS event page (event ID: us6000kdce). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2023, May 20, 2023). M7.1 Earthquake southeast of the Loyalty Islands — May 20, 2023. Retrieved July 24, 2023 from https://www.earthquaketracker.org/earthquakes/event/us6000kdce/