Geochemical samples applications

Examples of low temperature geochemical and environmental science applications of XAFS spectroscopy. Recent applications of XAFS spectroscopy to environmental and low temperature geochemical samples are reviewed by Brown et al. (1999c), Fendorf (1999), Day (1999), Brown and Parks (2001), Manceau et al. (this volume), Myneni... 

This summation pelds the ion-series spectrum for that compound, which is then matched, either manually or automatically, with the ion-series spectra of each class of compounds known to the system. Applications to environmental chemistry and to the analysis of complex geochemical samples seem to have been promising. 

LIBS has been also successfully applied to the analysis of geochemical samples [1485]. The most accurate information can be obtained for the relative concentrations of different elements in a sample. This is important, for example, for the classification of minerals on earth or in meteroites when it is not clear whether two different samples come from the same source. Also for archeological samples the precise knowledge of elemental composition is very helpful for the exact dating and assignment. The applications of LIBS has benefitted from the use of fiber optics which allows remote sensing, where the laser and detection systems are far away... 

Identification of sources of analytical bias in method development and method validation is another very important application of reference materials in geochemical laboratories. USGS applied simplex optimization in establishing the best measurement conditions when the ICP-AES method was introduced as a substitute for AAS in the rapid rock procedure for major oxide determinations (Leary et al. 1982). The optimized measurement parameters were then validated by analyzing a number of USGS rock reference samples for which reference values had been established first by classical analyses. Similar optimization of an ICP-AES procedure for a number of trace elements was validated by the analysis of U S G S manganese nodule P-i (Montaser et al. 1984). 

A national-scale geochemical survey of Australia is under way. It applies ultra low sampling density to transported and well-mixed outlet sediments, which are expected to represent the average composition of large catchments. The NGSA will provide the first complete, internally consistent geochemical data layer for Australia and is expected to find applications in energy and mineral resources exploration. 

Paulen, R.C., 2009. Sampling techniques in the Western Canada Sedimentary Basin and the Cordillera. In R.C. Paulen I. McMartin (eds.), Application of Till and Stream Sediment Heavy Mineral and Geochemical Methods to Mineral Exploration in Western and Northern Canada, Geological Association of Canada, GAC Short Course Notes 18, 41-59. 

The analytical approach and quality control system has been successfully applied in geochemical mapping projects. During the past 15 years, approximately 50,000 samples have been analysed for Pt and Pd. Some examples of applications are as follows ... 

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