Leaving the name in because Catherine Ulissey is promoting her husband, notorious archaeology kook Robert Schoch. As it says there, he's been on Rogan.

As for what they are talking about: https://en.wikipedia.org/wiki/Misra%C4%A7_G%C4%A7ar_il-Kbir

Misrah Ghar il-Kbir (informally known as Clapham Junction) is a prehistoric site in Siġġiewi, in the south of the Island of Malta, near the Dingli Cliffs. It is best known for its "cart ruts", a complex network of tracks carved in the rock. The age and purpose of the tracks is uncertain with estimates of their origins ranging from the Neolithic to Medieval times and all points in-between.

So, was it scorching plasma? Aliens? Or is the explanation simpler?

Research published in 2008 describes them as caused by wooden-wheeled carts eroding soft limestone. An analysis was made of the stresses that would have been caused by a cart which would fit the ruts. Professor Mottershead of Portsmouth University said "The underlying rock in Malta is weak and when it’s wet it loses about 80 percent of its strength. The carts would have first made tracks in the soil but when that eroded, the cartwheels ran directly on the bedrock, making it easier for other carts to follow the same tracks."