GeologyRocks

Roman historians Tacitus and Dio Cassius note that just before Boudica's revolt the statue of the goddess Victory in Colchester (then the political and religious capital of Roman Britain) rotated and fell over. 'Otherworldly groans' were heard and the sea 'turned blood red'. Boudica's followers interpreted this as divine approval for the rebellion and the Romans saw it as a bad omen.

The descriptions have been interpreted by Hull archaeologist Raphael Isserlin and BGS seismologist Roger Musson as signs of an earthquake. As well as the toppling statue, earthquakes can be accompanied by groaning sounds and the red sea colour could be the result of a turbidity current or cliff collapse triggered by the 'quake.

Colchester was hit on April 22nd, 1884 by a magnitude 4.7 earthquake which due to its shallow depth caused widespread damage (including 1,200 buildings and 31 churches) and strange noises were also reported. There were two deaths, one of shock (presumably heart attack) and the other was a woman called Mary Saunders who viewed the earthquake as a sign that worse was to follow that she drowned herself in the River Stour.

It is interesting that it looks like we can add Boudica's revolt to the destruction of Sodom and Gomorrah and the parting of the Red Sea to earthquake related events.