Bioturbation
Reworking of soil or other sediment by a living organism such as a worm.
Any animal that lives in or on sediments – that digs or burrows or simply
moves across the surface – will create some kind of disturbance in those
sediments.
In the broadest sense, any kind of sediment disturbance is bioturbation. Often,
however, the term is employed more restrictively to refer to the disruption
of fine sedimentary layering by digging organisms.
Palaeosol with traces of roots from the Maurine Red Marl Formation at Arques