Hi Ruby;
Perhaps this is the fact behind the story;
www.iberianature.com/material/megatsunami.html
That and a few quakes in the Atlantic
M 5.5, Azores, 2008 24 May Cumbre Vieja.
M6.4 23 May Central Mid Atlantic Ridge
The last time a significant portion of the Cumbre Vieja Ridge collapsed was in 1949.
Read the story, the facts are not as scary as the danger story, but do monitor the USGS earthquake page.
Earthquakes have been an interest since I was caught in a M 6.2, years ago, now I check the USGS data every waking hour, every day, first California and Nevada, then USA, then World.
Hope this helps you to sleep better.
M