Throughporosity

Throughporosity is a term used to describe the fraction of pore space in a material that forms a continuous, connected network capable of enabling fluid flow from one boundary to the opposite boundary. It represents the portion of total porosity that contributes to advective transport, distinguishing mobile, connected pores from isolated or dead-end pores that do not sustain long-range flow.

In practice, throughporosity is a measure of pore connectivity and is closely related to, but distinct from, overall porosity. A rock or porous medium can have high total porosity but low throughporosity if most pores are poorly connected, while high throughporosity indicates a more interconnected pore network that supports higher permeability and efficient fluid movement.

Throughporosity is important in fields such as hydrogeology, petroleum engineering, and material science because it largely governs permeability and transport properties. It influences groundwater recharge, contaminant spreading, oil and gas production, and the performance of porous construction materials.

Measurement and estimation of throughporosity can be approached through direct flow tests (permeability measurements), tracer breakthrough experiments, and imaging techniques such as micro-computed tomography or magnetic resonance imaging to visualize pore connectivity. Correlations with porosity and pore-throat size are often explored using models that separate connected (mobile) porosity from isolated porosity, acknowledging the role of tortuosity and pore geometry.

Notes: throughporosity is scale- and direction-dependent and may vary with loading, saturation, and rock type. It is a key concept for understanding how pore structure translates to fluid transport in porous media.