Soil
Soil Porosity and Permeability
GEO 101 LAB – Earth Science
July 26, 2014
Soil Porosity and Permeability
The focus of week three’s lab in Earth Science is to figure out the porosity and permeability of four different soil types: gravel, sand, potting soil, and soil from my back yard. This lab is designed to look at the porosity and permeability of these four soil samples. Porosity is basically the measure of how much of the soil volume is open space. Permeability is the measurement of how long and how easily water goes through soil.
Porosity Percentage Graph
Description of Sample Total Volume
(ml) Volume Remaining in the Graduated Cylinder
(ml) Pore Space Porosity (% pore space)
Gravel 100
45 55 29%
Sand 100
55 45 37%
Top Soil 100
25 75 14%
Your collected sample 100 35 65 21%
If I were an environmental engineer, I would recommend placing a drinking water well in gravel or sand because they are more permeable and they allow water to flow through more freely. Sand and gravel, are usually highly permeable. Sand and gravel have large spaces, or pores between particles where the water is stored. The large pores in sand and gravel are capable or yielding large quantities of water (Lutgens &Tarbuck, 2014). Sand, gravel, and other geological materials capable of transmitting and storing significant quantities of water are aquifers. Aquifers are commonly found in bedrocks sandstone or limestone and in overlying deposits like sand and gravel. Out of all the soil samples that were tested in this lab, gravel is the most permeable aquifer. Gravel allows water to move through it more freely letting contaminated groundwater travel longer distances without getting cleansed (Lutgens &Tarbuck, 2014).
Permeability Percentage Graph
Description of Sample Drainage Time
(sec) Amount of Runoff
(ml) Drainage Rate
(Amount of water drained/time) % Water Retained
((50ml –amount of runoff)/50)*100
Gravel
30.2 47 1.56 6%
Sand
60 40 0.67 20%
Top Soil
GEO 101 LAB – Earth Science
July 26, 2014
Soil Porosity and Permeability
The focus of week three’s lab in Earth Science is to figure out the porosity and permeability of four different soil types: gravel, sand, potting soil, and soil from my back yard. This lab is designed to look at the porosity and permeability of these four soil samples. Porosity is basically the measure of how much of the soil volume is open space. Permeability is the measurement of how long and how easily water goes through soil.
Porosity Percentage Graph
Description of Sample Total Volume
(ml) Volume Remaining in the Graduated Cylinder
(ml) Pore Space Porosity (% pore space)
Gravel 100
45 55 29%
Sand 100
55 45 37%
Top Soil 100
25 75 14%
Your collected sample 100 35 65 21%
If I were an environmental engineer, I would recommend placing a drinking water well in gravel or sand because they are more permeable and they allow water to flow through more freely. Sand and gravel, are usually highly permeable. Sand and gravel have large spaces, or pores between particles where the water is stored. The large pores in sand and gravel are capable or yielding large quantities of water (Lutgens &Tarbuck, 2014). Sand, gravel, and other geological materials capable of transmitting and storing significant quantities of water are aquifers. Aquifers are commonly found in bedrocks sandstone or limestone and in overlying deposits like sand and gravel. Out of all the soil samples that were tested in this lab, gravel is the most permeable aquifer. Gravel allows water to move through it more freely letting contaminated groundwater travel longer distances without getting cleansed (Lutgens &Tarbuck, 2014).
Permeability Percentage Graph
Description of Sample Drainage Time
(sec) Amount of Runoff
(ml) Drainage Rate
(Amount of water drained/time) % Water Retained
((50ml –amount of runoff)/50)*100
Gravel
30.2 47 1.56 6%
Sand
60 40 0.67 20%
Top Soil
References: Lutgens, F., & Tarbuck, E. (2014) Foundation of Earth Science: Chapter 3, Pearson Education Inc., Saddle River, NJ Stack, L. (2012) Soil & Plant Nutrition. Retrieved from http://www.umaine.edu/gardening/master-gardner/manual/soil/soil-and-plant-nutrition/