Stromatolites

Description:

Layered accretionary structures formed in shallow water by the trapping, binding and cementation of sedimentary grains by biofilm of microorganisms, especially cyanobacteria ( commonly known as blue-green algae) Stromatolites provide the most ancient records of life on earth by fossil remains which date from more than 3.5 billion years ago.

Habitat:

Hamelin Pool near Kalbarri WA. Shallow water.