Soil, Porosity and Permeability

Porosity refers to...

• the shape of the particles
• The sorting of the particles
• % of pore space in a material
• % of cement in a material

Impermeable materials...

• have an abundance of pores.
• let water in.
• have little to no pores.

Porosity is dependent on all of the following EXCEPT...

• Particle shape
• Amount of cement
• Sorting
• Hardness

Which of the following has the lowest porosity?

• Clay
• Silt
• Gravel
• Sand

Water flows through permeable materials ____________________ than impermeable materials.

• slower
• faster

If porosity is low then permeability is ______________.

• low
• high

The ___________________ the grain size, the faster the water will move through the soil.

• more mixed
• smaller
• larger

Poorly sorted soil...

• has low porosity
• has high porosity
• has high pore space
• means water will move through quickly

Well sorted soil...

• has low porosity
• has low pore space
• has high porosity
• means water will move through slowly

A sponge has high porosity.  A rock can have it too.  Porosity is...

• the inability to hold water
• the ability to hold water
• allowing water to pass through