An earth tremor measuring 1.3 on the Richter Scale has hit Highbridge.
The tremor struck at 2.52am on Sunday morning. Experts believe the 'epicentre' was 7km below the surface to the west of the hamlet of Alstone.
The British Geological Survey, which monitors UK earthquakes, said small tremors are not unusual in the area - a quake in December 2006 measured 1.6 on the Richter Scale.
A spokesman said: "There are actually about 200 in this country every year. Most go completely unnoticed by the public because they are so small."