Microfocus Computer Tomography (mu CT) is a non-destructive imaging techniq
ue that allows visualisation of internal features within non-transparent ob
jects such as sedimentary rocks. With resolution as good as 10 mu m in thre
e dimensions, this technique is highly superior to medical CT widely used i
n geology and material sciences. Superior resolution is achieved by decreas
ing the X-ray spot size, which allows a decrease in the penumbra effect and
an increase in primary magnification by placing the sample close to the X-
ray source. Since polychromatic X-ray sources are used, the technique is no
t free of artefacts. Application of filtering techniques is recommended to
circumvent these artefacts and to achieve good quality images for quantitat
ive analysis. Application of a dual energy approach allows quantification o
f density as well as effective atomic number distribution of internal featu
res. As the technique acquires data in 3D, mu CT provides an ideal tool to
link 2D thin-section petrography to 3D petrophysical measurements or to be
used within an upscaling approach. A number of applications and the use of
dual energy density and effective atomic number characterisations are prese
nted. Attention is also paid to some of the limitations of this technique.
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