A Perspective on the Evolution of Geoanalytical Techniques for Silicate Rocks

Progress in geochemical research is greatly influenced by developments in analytical technology and in this paper, the development of geoanalytical techniques over the last fifty years is reviewed, based in part on a previous study (Potts et al. 1993). From an evaluation of trends in techniques used for the bulk analysis of silicate rocks during recent years, the important future role of XRF and ICP-MS is apparent. However, it is concluded that the techniques that will be the most important in influencing progress in geochemical research in the future will be those based on microbeam analytical techniques. These techniques are increasingly capable of making the full spectrum of analytical measurements, traditionally undertaken on bulk samples, but on a microprobe scale to spatial resolutions that currently vary from sub-μm to about 50 μm. One way of evaluating future developments is to ask what might happen to various categories of techniques if key parameters such as sensitivity and detection limits were improved by, say, two orders of magnitude. Some suggestions are made describing the possible consequences of such an enhancement in analytical performance.