Radiocarbon marine shell

Taylor, R. E., Slota, P., Fraction Studies on Marine Shell and Bone Samples for Radiocarbon Analyses, In Radiocarbon Dating, pp. 422-432, Berkeley University of California Press, 1979. 

Figure 6. Radiocarbon content of modern pre-bomh marine shell from the west coast of North and South America, Data from Refs. 73 and 74. Values have been expressed with respect to 0.95 NBS oxalic acid standard and corrected in light of their values.

It is important to emphasize that a discussion of the problems associated with marine shell could be repeated for any sample type/geo-chemical environment where the contemporary radiocarbon values may not be in equilibrium with the atmosphere. In such cases, a specific contemporary standard must be used for each sample type or geochemical environment which can be related to the terrestrial biological radiocarbon standard. Special standards and/or correction values would, for example, be required for specifically defined oceanographic regions in the case of marine shell, standards for specific fresh water shell or gastropod geochemical environments, standards for Arctic and Antarctic specimens, and specific soil carbonate environments (75). 

Taylor, R. E., Berger, R., "Radiocarbon Content of Marine Shells from... 

MangerudJ. (1972) Radiocarbon dating of marine shells, including a discussion of apparent ages of Recent shells from Norway. Borens 1, 143-72. 

Berger R., Taylor R. E. and Libby W. F. (1966) Radiocarbon content of marine shells from the California and Mexican west coast. Science 153, 864-866. 

Plant remains and mollusk shells from marine Holocene layers in the central depression (layers containing Cerastoderma, station 15) have been dated by radiocarbon methods [16]. The results provided evidence of marine sedimentation being confined to the second half of the Holocene and permitted us to date some large regressive phases in the history of the Aral. Other studies have been performed in the central basin, including oxygen isotope analysis of carbonates in mollusk shells... 

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