Answer:
Porosity and permeability are two properties that describe the characteristics of a rock or soil that affect the flow of fluids through it.
Porosity refers to the amount of open space, or pores, within a rock or soil. It is typically expressed as a percentage of the total volume of the rock or soil and it is a measure of the ability of the rock or soil to hold a fluid.
Permeability, on the other hand, refers to the ability of a rock or soil to allow a fluid to flow through it. It is a measure of the ease with which a fluid can move through the pores of a rock or soil and it is usually measured in units of length squared (such as square feet or square meters).
Permeability affects the flow of groundwater because it determines how easy it is for water to move through the pores of the rock or soil. If a rock or soil has high permeability, water can flow through it easily and quickly. If a rock or soil has low permeability, water will have a hard time flowing through it and will move slowly.
In general, high permeability rocks and soils are considered to be good aquifers, while low permeability rocks and soils are not good aquifers. Therefore, permeability plays a crucial role in determining how much water can be stored and how fast it can be recovered from an aquifer.