In sedimentology, there are cases where sediments contain a huge amount of coprolites. These "coprogenic sediments" are common in marine environments, and are often the result of benthic organisms producing vast amounts of fine-grained excrement. For example, the Pelecypod Mytilus yields huge amounts of coprogenic mud, which completely surrounds it's biotope in tidal flats.

   However, if these coprogenic muds are not held together very well, wave action and currents will easily destroy them. On the other hand, if the muds are held together quite strongly they will form compact layers. Also to be considered are ellipsoidal fecal pellets produced by other benthic organisms, because they too will form layers of there own. This combination of ellipsoidal pellets and coprogenic muds are frequently found in the troughs of ripple marks in marine environments, or on muddy or sandy tidal flats.

NMC 40752 *

   These layers can be found in the neritic and even the abyssal. They are common in the recent, but such layers have also been found in the ancient. For example, an ancient layer was found in the Maestrichtian Stage in the Upper Cretaceous, in the Netherlands.

Back

Next