Surface characterization geological materials

SIMS is one of the most powerful surface and microanalytical techniques for materials characterization. It is primarily used in the analysis of semiconductors, as well as for metallurgical, and geological materials. The advent of a growing number of standards for SIMS has gready enhanced the quantitative accuracy and reliability of the technique in these areas. Future development is expected in the area of small spot analysis, implementation of post-sputtering ionization to SIMS (see the articles on SALI and SNMS), and newer areas of application, such as ceramics, polymers, and biological and pharmaceutical materials. 

Unlike laboratory chemistry, geological chemistry occurs in thermodynamically open systems. That is to say, there is flagrant exchange of materials and energy between the system and the environment Not only is the system as a whole not isolated from the environment, but the materials of interest are rarely isolated from each other. To further the complexity, interaction of mineral catalysts with those forms of energy most likely to affect surface-mediated reactions has barely been characterized in model systems. 

The characterization of the soil overburden at SRS as a fairly uniform sand to sand/clay layer of about 1000 feet thickness and having a shear wave velocity slightly larger than 1000 fps is consistent with the data collected at the site. This descriptiuii is also consistent with the geologic history of the area. As discussed in Section 6.1.5, a soils characterization program has been initiated to further document the near surface material properties at the rector site. 

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