M4.5 Earthquake 104 km NW of Castelo Branco, Portugal — November 7, 2021
2021-11-07 18:16:40 UTC (2021-11-07) · approx. 4:16 PM UTC-2 local
On November 7, 2021 at 18:16 UTC, a magnitude 4.5 shallow crustal earthquake struck 104 km NW of Castelo Branco, Portugal, at a depth of 10.0 km and coordinates 39.0912°, -29.6740°.
Physical scale: An earthquake of magnitude 4.5 releases seismic energy equivalent to roughly 85 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 767 m — a useful intuition for the size of the slip patch on the fault.
Earthquake Details
-29.6740°E
Technical Information
Common Questions
How strong was the magnitude 4.5 earthquake near Castelo Branco, Portugal?
The magnitude 4.5 earthquake that struck 104 km NW of Castelo Branco, Portugal on November 7, 2021 at 18:16 UTC had a depth of 10.0 km. For context, this was a light earthquake commonly felt near the epicenter.
Where did the earthquake occur?
The earthquake epicenter was located at 39.0912°, -29.6740°, which is 104 km NW of Castelo Branco, Portugal.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.5 earthquakes can continue for several days and gradually diminish over time.
Authoritative source: USGS event page (event ID: us7000ft9d). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, November 7, 2021). M4.5 Earthquake 104 km NW of Castelo Branco, Portugal — November 7, 2021. Retrieved January 15, 2022 from https://www.earthquaketracker.org/earthquakes/event/us7000ft9d/