An earthquake measuring 4.2 on the Richter scale was felt in the Lagos area on March 31 at about 4am.
The earthquake epicentre was located 74 kilometres west off Cape St. Vincent in Sagres.
According to the Portuguese Institute for Meteorology, no damage to property or injury to people was reported.
The earthquake had the highest magnitude of the 42 registered in March alone along Cape St. Vincent.
Later that day, at 3.13pm, another earthquake was felt in the area but registering less magnitude (1.6 on the Richter scale).