People living in parts of Staffordshire reported an earthquake in the early hours of Wednesday.
The tremor measured 2.6 on the Richter scale and its epicentre was directly beneath Stoke-on-Trent.
Residents in Newcastle, Birches Head, Basford and Sneyd Green contacted BBC Radio Stoke to say they had felt it.
The British Geological Survey (BGS) said although the size of the quake was not uncommon, it was unusual it had been felt by so many people.
Near surface
BGS seismologist Glenn Ford told BBC News: "We get about 20 to 30 events of that size every year and only 10% of earthquakes are recorded.
"What makes this slightly more unusual is that it was felt so strongly by so many people. This could be because it was closer to the surface."
He added: "Stoke-on-Trent has historically had a lot of activity. There was a period when there were dozens of earthquakes every day - a lot of it related to the mining in the area."
Mr Ford said that an hour before the earthquake in Staffordshire, York was also affected by an earth tremor which measured 2.4 on the Richter scale.