The website says: “On the afternoon of 26 January 2012, from around 16:05 UTC, the BGS began to receive information from the media, the police and several residents in towns and villages to the in and around east Cumbria, North Yorkshire and West Yorkshire, who reported that they felt what many had thought to have been an earthquake at sometime around 16:00 UTC. Reports described “massive bang and then a rumble and everyones house shook but only for a second “, “it sounded like a crash or explosion “, “I felt it shake me up to the knees and quite violently ” and “it sounded more like a boom rather than a blast”.

“Data from the BGS seismic networks in the region were examined and signals consistent with a possible sonic origin were recorded at 15:56 UTC on our seismic station HPK in the Yorkshire area.  The observations received are similar to those which have been received previously for sonic booms.

“The RAF have since put an announcement on the MOD website informing the public that, in the run-up to the Olympic Games, a training exercise is taking place in the area of the Yorkshire Dales. Further information on this can be found at http://www.raf.mod.uk/news/archive/olympic-security-26012012.”

For the full piece on the British Geological Survey website go to: 

http://earthquakes.bgs.ac.uk/earthquakes/recent_events/sonic_event_yorkshire_dales_260112.html