Mineralogy environmental controls

On a relative basis, i.e. residues per 1000, there is virtually no one species like the other. In contrast, different shell samples from the same species and obtained from the same natural habitat yield identical amino acid patterns. It is of interest that (1) the structure of carbonates (aragonite-calcite-vaterite), (2) the content in trace elements, and (3) the stable isotope distribution are markedly effected by fluctuations in salinity, water temperature, Eh/pH conditions, and some anthropogenic factors. The same environmental parameters determine to a certain degree the chemical composition of the shell organic matrix. This feature suggests a cause-effect relationship between mineralogy and organic chemistry of a shell. In the final analysis, however, it is simply a reflection of the environmentally-controlled dynamics of the cell. 

Bar-Matthews, M., Matthews, A., and Ayalon, A., 1991, Environmental controls of speleothem mineralogy in a karstic dolomitic terrain (Soreq Cave, Israel), J. Geol 99 189-207. 

Mineralogical characterization of microbial ferrihydrite and schwertmannite and non-biogenic Al-sulfate precipitates from acid mine drainage in the Donghae mine area, Korea. Environmental Geology, 42, 19-31. Knorr, K. Blodau, C. 2007. Controls on schwertmannite transformation rates and products. Applied Geochemistry, 22, 2006-2015. 

Due to their persistent silica skeletons and their diversity, diatom remains provide a good record of past and present environmental conditions. Cameron (2004) recently showed that they could be used to compare samples that had been in contact with water and for the investigation of time of death in drowning. Through the recent advances in analytical quality control and use of multivariate statistics, their use in forensics is likely to develop further. In a similar way, phytoliths (the plant opal silica structure that accumulates in some plants) have been used to differentiate soils with otherwise similar mineralogy (Marumo and Yanai 1986). 

Banfield J. F. and Welch S. A. (2000) Microbial controls on mineralogy of the environment. In Environmental Mineralogy, European Mineralogical Union (eds. D. J. Vaughan and R. A. Wogelius). Budapest University Press, Budapest, vol. 2, pp. 173-196. 

Ritchie A. I. M. (1994) Sulhde oxidation mechanisms controls and rates of oxygen transport. In The Environmental Geochemistry of Sulfide Mine-wastes (eds. J. L. Jambor, and D. W. Blowes). Mineralogical Association of Canada, Nepean, ON, vol. 22, pp. 201-246. 

Some of the differences are no doubt related to the con5)lexity of the mercury system including the various forms of mercury produced under varying environmental conditions and also on the lack of laboratory and field control, particularly in relation to detailed and accurate characterization of sediments. Sorption phenomena are strongly dependent on the t5q>e (mineralogy, chemical species, etc.) and also on the total available surface area of adsorbing materials. These variables must be accurately determined if reproducible results are to be found in any mercury sorption study. 

Mineralogical analysis allows a detailed systematic study of the inhaled particles or fibers retained in human lungs. It is a powerful tool that complements the other methods used to investigate occupational or environmental exposures and related diseases. There are, however, a number of different methods available, and it is important to be aware of the technical factors and intrinsic limitations that could influence the results. The choice of the method will depend on the question to solve, the sample type and amount and the available analytical tools. The more sophisticated techniques, such as electron microscopy, are only used in a number of specialised laboratories. Currently, each laboratory should have its own reference values obtained from local control populations. 

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