Diagenesis a Critical Area for Further Work

All geochemical paleoproxy tools are subject to this particular challenge. Even when a particular environmental or biological variable has been recorded directly and straightforwardly in sediment, preservation of that clear chemical 

Given these observations in natural samples, systematic investigations of which processes can reset metal isotope ratios, how those processes shift isotope records, and what signs can be used to detect, and possibly correct for, the effects of diagenesis are absolutely essential. Some of the experimental and theoretical studies discussed above have yielded results that will help build a fundamental understanding of how diagenesis affects stable isotopic signatures of metals, but to 

Johnson C.M., Beard B.L, Roden E.E., Newman D.K., Nealson K.H. (2004) Isotopic constraints on biogeochemical cycling of Ee. Rev. Mineral. Geochem., 55, 359 08. 

and Rouxel, O. (2007) Metal stable isotopes in paleoceanography. Annu. Rev. Earth Planet. Sci, 35, 

Johnson C.M., Beard B.L., and Roden E.E. (2008) The iron isotope fingerprints of redox and biogeochemical cycling in modem and ancient earth. Annu. Rev. Earth Planet. Sci., 36, 457-493. Montero-Serrano, J.-C., Martinez-Santana, M., Tribovillard, N., 

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