Trace fossil Burrow

Trace or not?

This is probably the most obscure trace fossil in our collection! Is it a disc-shaped structure or a spiral screw? It’s hard to tell. Sponges or sea-anemones might have produced such sea floor traces, but an alternative suggestion is that they might be formed by sediment falling into a cavity, perhaps created from the rotting remains of an animal. Some people question if such specimens are trace fossils at all – suggesting that they might have been produced by fluids or gas escaping through the soft sediment.

This is the first find of its type from the Kimmeridge Clay (they are more common in north-east England Lower Jurassic rocks). 

Find out more on the trace fossils page.

Common name

Trace fossil Burrow

Scientific name



Trace Fossils


Kimmeridge Clay Formation

Time period

Upper Jurassic


150 million years

Where found

Kimmeridge {module Kimmeridge Bay safety warning}

Found by



Dorset County Museum, Dorchester

Accession number