In GeoDict, different methods are available to determine the size of a pore. Before describing them in more detail we answer the following questions:

• What is a pore?
• What is a pore body and what is a pore throat (or pore neck)?

Structures in GeoDict may consist of solid voxels and non-solid voxels. The non-solid parts are also called pore space. The pore space may be empty or filled with a fluid material.

The transition from the term pore space to the term pore is not that trivial. For a pore space that is convex, e.g., it has the shape of a sphere, the whole pore space can be called a pore. But for more arbitrary shaped geometries, we need two other definitions.

A Pore Body is a relatively large part of the pore space while a narrower part is called a Pore Throat. To get an idea, imagine the pore space to be a network of channels, where pore throats divide larger parts of the pore space but still connect those parts. When talking about the term pore, often the pore body is meant. However, there can also be pore space which is not connected to any other pore space. This pore space is called Closed Pores.

Now, we can go into more detail about how the three methods (Granulometry, Porosimetry and Identify Pores) for determining the pore body sizes in GeoDict work. We will look at the structure shown above, which is periodic in the y-direction and has a voxel length of 0.5 µm and visualize the results for each method. By pure visual investigation we can observe three pore bodies that are connected via pore throats.

Afterwards, we explain how the two methods to determine pore throat sizes (Percolation Path and Bubble Point) work.