Organic matrix taphonomy in some molluscan shell microstructures

The organic matrix of selected specimens of cephalopods and bivalves was observed by scanning electron microscopy upon shell sections etched and preserved by critical point drying. For specimens ranging in age from Pennsylvanian to Recent, it was noted that physical preservation of the organic matrix was not strongly dependent on age. Matrices were also found to have degraded at different rates in different shell microstructures, even in the same shell. The type of degradation had also varied, even for the same kind of microstructures. The occurrence of preserved organic matrix may be more widespread among molluscan fossils than commonly thought.