New algorithms in 3D image analysis and their application to the measurement of a spatialized pore size distribution in soils

We introduce a skeletization method based on the Voronoi diagram to determine local pole sizes in any porous medium. Using the skeleton of the pore space in a 3D image of the porous medium, a pole size value is assigned to each voxel and a reconstructed image of a spatialized local pore size distribution is created. The reconstructed image provides a means for calculating the global volume versus size pore distribution. It is also used to carry out fluid invasion simulation which take into account the connectivity of and constrictions in the pore network. As an example we simulate mercury intrusion in a 3D soil image. (C) 1999 Elsevier Science Ltd. All rights reserved.