Determination of the silicon content of geological materials by reactor fast neutron activation analysis.

Determining the silicon concentration of geological materials is desirable because the silica (SiO2) content is an important criterion often used in their classification and in assessing petrogenesis. A rapid, non-destructive, approach for measuring silicon in rocks by reactor fast NAA using a B4C shield and the transmutation reaction 29Si(n, p)29Al is presented that is competitive with other commonly applied analytical techniques. In addition to quantifying silicon the simultaneous determination of U and Co (largely by epithermal NAA), and Mn and V (by activation predominantly with the residual thermal neutron flux) is also generally possible. Silicon, Mn, U, V and Co concentrations are reported for a number of rock standards demonstrating the utility of the method. [ABSTRACT FROM AUTHOR]