Bioturbation and trace fossils

Bioturbation of sediments is one of the most important sources of paleoecological information from the stratigraphic and fossil record. Organisms utilize a variety of behaviors when they interact with the environment. The trace fossil record of the different types of behaviors can commonly be found in marine and terrestrial sedimentary rocks and provides a vast source of information on how animals lived and interacted with each other and the physical and chemical environments surrounding them. This chapter shows the various processes which trace fossils and other biogenic sedimentary structures in marine pelagic/hemipelagic muds pass through as they become a permanent part of the lithosphere. Several schemes have been proposed to assess the amount of bioturbation recorded in sedimentary rock as reflected by ichnofabric. Bioturbation has been an active process in terrestrial environments since animals colonized land by the Ordovician and various other nonmarine settings later in the Paleozoic.