"And thou, all-shaking thunder,
Smite flat the thick rotundity o' the world!
Crack nature's moulds, an germens spill at once,
That make ingrateful man!"

-King Lear,
Act 2, Scene 3, King Lear
William Shakespeare

Friday, March 13, 2015

Making Waves

When a tsunami hits, there is nothing in the world that can stop the powerful wave from destroying everything in its path. If you've watched the news at all in the last ten years, you'll know what a tsunami looks like, and just how destructive it can be. But do you know how they begin?

A Tsunami can be caused by natural occurrences, whether that be a submarine landslide, the impact of an asteroid or meteorite, an earthquake that causes the shifting of the seafloor, or an underwater volcano (Keller and Devecchio, 102-109.)
A tsunami in Great Britain is very unlikely 
thanks to its position on the Eurasian plate.
(photo: Britishnationalparty.com)


The Lisbon tsunami and fire, 1755
(Glogster.com)

When reading about Great Britain, I was unsurprised to find that the British Isles are not really at risk of tsunamis, once again thanks to their placement on the Eurasian tectonic plate. According to the British Geological survey, there is evidence that Great Britain did suffer at least one tsunami about 8000 years ago. Thanks to geological records, scientists believe that a submarine earthquake off the coast of Norway sent waves toward the shores of Britain.

According to the Encyclopedia Brittanica, a magnitude 8 earthquake originating along the Atlantic faultiness created a tsunami powerful enough to destroy the city of Lisbon, Cornwall in 1755. With 20 foot waves, the tsunami destroyed 12,000 buildings and killed 60,000 people in the city alone.

Today, we know it is unlikely that Great Britain would be at risk of an earthquake for a few reasons. First, that the earthquakes which take place along the nearest plate boundary (the Atlantic Ridge) are too small and too far away to cause any peril. Second, that Britain hardly experiences earthquakes large enough to cause harm, given that the largest one recorded in British history was a 6.1  magnitude. It is for these reasons that there is currently no national tsunami warning system.