An earthquake with its epicenter approximately 510 kilometers north-northwest of the island of Porto Santo was recorded by the Mainland Seismic Network at 02:29 today, the Portuguese Institute for Sea and Atmosphere (IPMA) announced.
The earthquake did not cause any personal or material damage and was felt with a maximum intensity of II-III (Modified Mercalli scale) in the Madeira region, with even lesser intensity reported in Setúbal and Lisbon regions.
According to the Richter scale, earthquakes are classified by magnitude as follows: micro (less than 2.0), very small (2.0-2.9), small (3.0-3.9), light (4.0-4.9), moderate (5.0-5.9), strong (6.0-6.9), major (7.0-7.9), great (8.0-8.9), exceptional (9.0-9.9), and extreme (when above 10).
#Earthquake (#terramoto) M5.6 strikes 571 km NW of #Funchal (#Portugal) 5 min ago. More info: https://t.co/3nxm3Zc336
— AllQuakes – EMSC (@EMSC) July 25, 2025
The Modified Mercalli scale measures the “degrees of intensity and respective description.”
Earthquakes are classified by magnitude as follows: micro (less than 2.0), very small (2.0-2.9), small (3.0-3.9), light (4.0-4.9), moderate (5.0-5.9), strong (6.0-6.9), major (7.0-7.9), great (8.0-8.9), exceptional (9.0-9.9), and extreme (above 10).
A maximum intensity of II on the Modified Mercalli scale indicates that the tremor “can be felt by people at rest on upper floors of buildings.”
With an intensity of III, considered weak, the tremor is felt indoors, and pendulum-like objects sway, causing a “vibration similar to that produced by the passage of heavy vehicles,” as detailed by IPMA on its website.
