M5.5 Earthquake near central Mid-Atlantic Ridge — August 9, 2020
2020-08-09 12:42:13 UTC (2020-08-09) · approx. 10:42 AM UTC-2 local
Felt by 97 people across nearby locations.
On August 9, 2020 at 12:42 UTC, a magnitude 5.5 shallow crustal earthquake struck near central Mid-Atlantic Ridge, at a depth of 10.0 km and coordinates 0.9296°, -27.7257°. The earthquake was reported felt by 97 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 2.7 (weak). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected.
Physical scale: An earthquake of magnitude 5.5 releases seismic energy equivalent to roughly 3 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 3.8 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 97 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
Earthquake Details
-27.7257°E
Technical Information
Common Questions
How strong was the magnitude 5.5 earthquake near central Mid-Atlantic Ridge?
The magnitude 5.5 earthquake that struck near central Mid-Atlantic Ridge on August 9, 2020 at 12:42 UTC had a depth of 10.0 km. It was felt by 97 people with maximum shaking intensity of MMI 2.7 (weak). For context, this was a moderate earthquake that could be widely felt.
Where did the earthquake occur?
The earthquake epicenter was located at 0.9296°, -27.7257°, which is near central Mid-Atlantic Ridge.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.5 earthquakes can continue for days to weeks and gradually diminish over time.
Actions
Authoritative source: USGS event page (event ID: us6000bbh7). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2020, August 9, 2020). M5.5 Earthquake near central Mid-Atlantic Ridge — August 9, 2020. Retrieved December 22, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000bbh7/