1. Porosity, Permeability and Ground Water
Don’t let it slip through your brain!!
HeHeHe

2. Porosity
porosity:
the percentage of rock or sediment that consists of voids or openings
Equation:
Porosity (%)= amount of pore space/ amount of substance

3. Porosity The porosity of an object depends on three things:
The packing of the particles
The sorting of the particles
The shape of the particles
Loosely packed
rounded
Closely packed
Angular

4. Porosity Tight packing reduces porosity
Poorly sorted materials made up of particles of various sizes have a lower porosity because the smaller particles occupy the pore spaces between the larger particles.
Round particles are more porous than materials made up of angular or irregularly shaped particles (puzzle pieces).

5. POROSITY

6. Permeability
permeability: the ability of a soil to transmit water through it.
porous: a rock that holds much water
permeable: a rock that allows water to flow easily through it
impermeable: a rock that does not allow water to flow through it easily

7. Factors that Affect Permeability
The rate of permeability depends on
the size of the pores
How the pores are connected
High permeability: large pores that are well connected
Sand
Low perm.: small pores that are not well connected.
Clay

8. PERMEABILITY

9. Capillarity Capillarity:
The ability of a soil to draw water upward into tiny spaces between soil grains.
Soil composed of very small particles show the most capillarity.
Paper towel in water.

10. Ground Water
ground water: the water that lies beneath the ground surface
It fills the pore space between grains in bodies of sediment and clastic sedimentary rock, and filling cracks and crevices in all types of rock
source of ground water is rain and snow that falls to the ground a portion of which percolates (bubbles) down into the ground to become ground water

11. Ground Water Vocab. Words
Evaporation:
The process when water changes from a liquid to a gas
Transpiration:
“sweat of plants”; when green plants release water vapor as a byproduct of photosynthesis
Sublimation:
Of snow and ice, which can become water vapor without passing through the liquid state.

12. The Water Cycle

13. Groundwater Zones Ground Zone of Aeration Natural filter for water
Water Table
Larger the water table:
Deeper the well
Zone of Saturation
Impermeable Bedrock

14. The Water Table (cont.)