The Case for Large Earthquakes Felt in the UK in Historical Times - Historical Seismology: Interdisciplinary Studies of Past and Recent Earthquakes - page 191

The same is true of the Annals of Loch C´e(Farber, 2005), the Annals of Connacht
(Bambury, 2001) and the Annals of the Four Masters (Ryan, 2002). None of these
chronicles mention the Welsh earthquake of July 1534 which was definitely felt in
Dublin (Ware, 1662).
5.3 20 January 1607
In January of 1607 a sudden inundation in the Bristol Channel flooded an area of
countryside around the town of Burnham-on-Sea to a depth of 3-4 m, and caused
damage at Barnstaple, Bridgewater, Bristol, Glastonbury and Kingston Seymour
(Horsburgh and Horritt, 2006); South Wales was also affected (Fig. 4). There was
some loss of life. It has been suggested (Bryant and Haslett, 2003; Disney, 2005) that
this flooding was due to a tsunami, though no earthquake is reported as having been
felt on this date. An earthquake is known to have affected Barnstaple and the adja-
cent area on 12 May 1607 (Musson, 1989) and it would be surprising if this small lo-
cal event were known and a more generally felt larger one very close in time was not.
Therefore, if this event was a tsunami, it must have been caused by an earthquake
sufficiently far offshore not to have been felt in England. One can posit an epicentre
Fig. 4 Water symbol: places affected by the inundation of 20 January 1607. Lozenge: felt reports
of the 12 May 1607 Barnstaple earthquake