Solved: The Mystery of The Loch Ness Monster

Loch Ness is one of the most famous and most beautiful of places in Scotland.  Part of this fame rests on the repeated allegation that the loch contains a monster, perhaps a throwback to the Pleistocene era. 

What are the facts?

Loch Ness is a large and enigmatic, deep, freshwater loch. Loch Ness extends for approximately 37 km (23 miles) into the Scottish Highlands to the southwest of Inverness. The waters of Loch Ness are cold, dark and deep.  These waters have leached from the local moors and contain many finely suspended peat particles.  Within five feet of the surface the waters are black. 

Loch Ness lies on a geological fault line known as the Great Glen which runs from Inverness to Fort William.  By surface area Loch Ness is second in size to Loch Lamond.  By volume Loch Ness is so deep that it contains more freshwater than all the lakes in England and Wales combined. The average depth of the loch is 142m (430ft). In 1992 a sonar survey identified the deepest point to be 240m (786ft). To put this into context, at the average depth the loch could submerge the great dome of St Paul with 70ft to spare.  At the deepest point the loch contains a column of water that would reach the 60th floor of the Empire State Building.  Below that lies a layer of sediment at least 25m thick and  a layer of clay before the bedrock is reached.

Here, the mysteries begin.  Lets go back to a time some 400 million years ago. The Atlantic Ocean had yet to form, Canada was close to Scandinavia, and the great land masses of Laurentia and Baltica were in collision. The fault line passed from the Great Glen south into Northern Ireland and north to the Shetland Isles where it becomes obscured. The same fault can be traced through Newfoundland to the Gulf of St Laurence. The collision formed the Highlands of Scotland and the mountains of Scandinavia.  Despite erosion, from these long ago events, the mountains of Scandinavia are still formidable leading geologists to believe that these were once the highest mountains ever formed on Earth and may have extended to 10km in height.  As a land form, the fault along the Great Glen looks like a rift valley. In time, particularly during the glacial periods associated with the ice age, the mountains have eroded and dammed the glen that forms Loch Ness, Loch Lochy and Loch Oich.  These Lochs were formed about 12,000 years ago when the ice retreated.  By that time the age of the dinosaurs had passed.  Considering the age of the Loch, I do not think it likely that it contains a monster from the age of the dinosaurs.