Fig. 5. (a) Original grey value x-ray computer tomography image (darker values correspond to less dense regions) of a horizontal core cross section (Core 1 of the 0.5- to 0.6-m layer), (b) binarized and opened x-ray CT image, (c) overlay of concentration map and binarized CT image (same cross section) from which identified unstained large pores are removed, and (d) map of distances to the nearest large pore (darker values correspond with larger distances). (e–h): same as (a–d) for a horizontal cross section in Core 1 from the 0.2- to 0.3-m layer.
