Tremors caused by an earthquake under the ocean to the west of Peniche shook locals on the immediate west coast and as far away as Lisbon late this morning.
The shock was felt in several areas of the capital but is not known to have caused any injury.
The earthquake measured 4.1 on the Richter scale and took place bang in the middle of the area covered by the Mexinhao concession, owned by Galp/Repsol/Partex and Kosmos.
Portugal’s weather service reported that the earthquake occurred at 12:44 and the epicenter was located about 80 kilometers west of Peniche in the 230 kilometre long Nazaré Canyon which sinks to a depth of 5,000 metres.
The canyon is part of the EU HERMES project using a remotely operated vehicle to investigate the specialised canyon ecosystem and the way in which the canyon influences and is affected by local ocean circulation.
The Canyon’s sub-sea terrain naturally causes very high breaking waves - as seen across the world when in November 2011, the Hawaiian surfer Garrett McNamara surfed a record breaking 24 metre wave and a 30 metre wave in 2013.
The site of the earthquake is in one of Portugal’s many oil exploration blocks. Anti-oil and gas campaigners say that the area is naturally fragile and these earthquake events will happen – but the last thing needed is for them to be provoked by drilling and extraction of oil.