Geologists use the term 'porosity' to describe the spaces between sediment grains where groundwater exists. Aquifers with high porosity and permeability are ideal for water wells, and the water table marks the transition to saturated conditions.
The term geologists use to describe where groundwater exists between sediment grains is porosity. Porosity indicates the volume of open spaces within rock or sediment and is crucial for the storage of groundwater. Sedimentary rocks like sandstone usually have high porosity because of the considerable space between the individual grains.
An aquifer is a geological formation that can store and transmit groundwater effectively, generally due to its high porosity and permeability. The water table signifies the boundary between the unsaturated zone above and the saturated zone where pore spaces are fully filled with water.
Overall, porosity is critical to the groundwater storage, while permeability determines the ease with which water can flow through the geological materials. To install a new water well, locating a layer with both high porosity and permeability is essential, and it is usually found above the water table in an unconfined aquifer.