The British Geological Survey says there was a magnitude 5.4 earthquake in the area in 1984.
It describes that year's event as "significant".
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It will be a dry night with clear spells for all of us, but the south-easterly wind will increase, becoming rather windy by morning.
Hundreds of campaigners are marching through the streets of Cardiff calling for the city's grassroots music venues to be protected.
People in Wales living with cancer face losing over £500 a month in income after diagnosis, according to Macmillan Wales.