When a tsunami hits a coastline, it is strong enough to chew up lots of debris, rocks and sand, which it then drops onto the land as it retreats back to the sea. Thousands of years later, these large sand debris layers will have turned to rock. These provide evidence of past tsunami events!

Tsunamis can travel inland very quickly, and can tear up vegetation before pulling it back as debris towards the coastline. Moss and chunks of peat are often carried back to shore. They contain carbon which can be dated to provide an estimated age for tsunami events! Sea level in the area has lowered since the tsunami because Scotland is bouncing upwards now that it is relieved of the weight of the ice. This makes it so much easier to find and analyse some of the evidence of tsunamis, such as debris layers and vegetation!