Phase segmentation in deformed medium
What is visually striking is that even a very small density contrast can be very effectively imaged. Shown above, the small density contrast between calcite (red, density 2.71 g/cm3) and quartz (blue, 2.66 g/cm3) is enough to perform an efficient segmentation, and therefore quantify the amount of each phase present. We can also represent textural alteration using segmentation. Shown on the left is an X-CT image of a pseudotachylite, which is a feature where part of the initial rock (grey) is molten (black). Overall, there is no variation in density, but grain size change enhances the diffraction of x-rays, leading to an efficient segmentation of the intact rock (blue) and its molten part (orange).
Figure: Cement-grain segmentation
Figure: Melt texture (pseudotachylite)