Glossary term
stromatolite
Definition
A mound-shaped structure formed in shallow water by alternating layers of carbonate or silicate sediment (mud that becomes trapped in the algae) and algal mats that become fossilised over time. Mounds over a metre high have been found. Stromatolites are widely distributed and contain some of the oldest recorded forms of life from over 2–3 billion years ago. They continue to form today, especially in Australia.