The Loch Ness Monster is a legend that a monster lives in a Scottish lake of the same name. Sightings and photos have surfaced for almost 100 years of the creature, including tremors in the lake and swirling bubbles to prove its existence.

Now, an Italian geologist says that the shaking ground and bubbles are caused by an active fault underneath Loch Ness, and are not signs of a monster living beneath the water.

Luigi Piccardi says the Great Glen fault system is the reason sightings have been reported of the legendary beast, according to Scientific American, NBC News reports.

"There are various effects on the surface of the water that can be related to the activity of the fault," Piccardi said in an interview published in the Italian newspaper La Repubblica.

For even more evidence, Piccardi claims that the reported Loch Ness monster sightings coincided with periods of seismic activity over the years. "We know that this was a period (1920-1930) with increased activity of the fault. In reality, people have seen the effects of the earthquakes on the water."

The Great Glen fault is more than 62 miles (100 kilometers) long. The Daily Mail reports that the fault has been responsible for several minor earthquakes over the past few centuries, usually of magnitude 3 or 4. Earthquakes were recorded in 1816, 1888, 1890 and 1901.

The Loch Ness monster, sometimes referred to as "Nessie," became an internationally-known legend in the 1930s, when a London surgeon named Kenneth Wilson took a picture of a serpentine head and neck in the Loch Ness lake. Decades later, however, that image was revealed to be a hoax.

No scientific evidence proves the existence of Nessie. However, this hasn't stopped sightings being reported in Scotland. In 2012, a boatman named George Edwards claimed he saw and photographed the monster. Skeptics believe his picture shows a floating log or a large fish, NBC News reports.