The Hydrological (Water) Cycle and Drainage Basin Systems Practice Test

Porosity is the rock’s capacity to hold water in its pore spaces because it measures the fraction of rock volume that is void space where water can reside. This storage potential depends on how much open space the rock has, regardless of how quickly water can move through it. The other terms describe different aspects: infiltration capacity is about how fast water can enter the surface, baseflow relates to the groundwater contribution to streamflow, and the water table marks the upper boundary of saturated groundwater. So porosity directly describes the amount of water a rock can store in its pores.