The tremor was the largest earthquake to affect the UK since the 1984 Llŷn Peninsula earthquake , which measured 5.4 on the Richter scale . The British Geological Survey gave the earthquake a reading of 5.2 ML , while the United States Geological Survey reported it measured 4.8 Mb . The French Atomic Energy Commission estimated the magnitude was 5.4 ML
1984 Llŷn Peninsula earthquake
1984 Llŷn Peninsula earthquake
2008 Market Rasen earthquake