The favourable reception given to the first (1996) edition of this book suggests that the joint treatment of electron microprobe analysis (EMPA) and scanning electron microscopy (SEM) with a specifically geological slant has been found to serve a useful purpose. It was therefore decided to proceed with this second, revised and updated, edition. The inclusion of both EMPA and SEM can be justified on the grounds that the instruments share much in common and their functions overlap: SEMs fitted with X-ray spectrometers are often used in analytical mode, while EMP instruments, though designed primarily for analysis, also have imaging functions similar to those of the SEM.
The capabilities of the computers used both for instrument control and for data processing have increased greatly since the first edition. Whilst this allows more sophisticated software functions, it does not diminish the need to understand both the operating principles of the instruments and the factors controlling the results, the explanation of which is the main purpose of this book. Digital rather than analogue imaging is now the norm, with concomitant advantages provided by image processing and image analysis techniques. The increasing use of ‘false’ colour images in various forms is reflected in an expanded colour section in this edition. Significant instrumental developments include the increasing adoption of field emission electron sources, which are especially beneficial for high-resolution SEM applications. Also, variablepressure or environmental SEMs are more commonly used. In addition, interest in ancillary techniques such as cathodoluminescence and electron backscatter diffraction has grown.