"In Boulby the rocks were formed around 250 million years ago, in a giant inland sea." MASE Scientific Coordinator Charles Cockell said. "We think the polygonal shapes are connected to the expansion of salt when the sea periodically dried out, similar to the processes we see in places like Death Valley in California today. These features are similar to some environments we see on Mars. We suspect that the rims contain clay, iron and organics and we want to test the hypothesis that they contain signatures of life."