Shocks from the earthquake were felt throughout Europe[6][7] as far as Finland and North Africa, and according to some sources even in Greenland[8] and in the Caribbean.[9] Tsunamis as tall as 20 metres (66 ft) swept the coast of North Africa, and struck Martinique and Barbados across the Atlantic. A three-metre (ten-foot) tsunami hit Cornwall on the southern English coast. Galway, on the west coast of Ireland, was also hit, resulting in partial destruction of the "Spanish Arch" section of the city wall. At Kinsale, several vessels were whirled round in the harbor, and water poured into the marketplace.[9]
Although seismologists and geologists have always agreed that the epicentre was in the Atlantic to the West of the Iberian Peninsula, its exact location has been a subject of considerable debate. Early theories had proposed the Gorringe Ridge until simulations showed that a source closer to the shore of Portugal was required to comply with the observed effects of the tsunami. A seismic reflection survey of the ocean floor along the Azores–Gibraltar Transform Fault has revealed a 50 km-long thrust structure southwest of Cape St. Vincent, with a dip-slip throw of more than 1 km. This structure may have created the primary tectonic event.[10]