Soil Analysis

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Soil Analysis
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Soil Analysis

• Objectives
• Understand physical characteristics of soil
• List three physical characteristics of soil
• Determine the density of soil samples using the
  density gradient tube

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Properties of Soil

• Soil includes disintegrated material that is
  found on or near the Earths surface
• Soil can include rocks, minerals, vegetation,
  animal matter, glass, paint chips, asphalt, brick
  and cinders.

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How is Soil Analyzed

• Color comparisons of dry samples under identical
  conditions
• Microscopic examination for debris
• Geologically for rocks and minerals
• Density-gradient tube technique

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How is Soil Analyzed

• Color comparisons of dry samples under identical
  conditions
• Microscopic examination for debris
• Geologically for rocks and minerals
• Density-gradient tube technique

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Density Gradient Tubes

• Composed of varying densities of two different
  liquids
• The particles of soil sink to the portion of the
  tube that has a density of equal value and then
  the particles are suspended in that spot.
• The low density is at the top of the tube and the
  liquid becomes more dense as you travel down the
  tube
• Distribution patterns from several samples can be
  compared.

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Density Gradient Tube Examples

• Examples of Density Gradient Tube Results
• Golf Football Park
  CrimeScene
• Course Field

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Crime Scene

• Someone broke into the school last night and
  raided the student lockers. The only evidence
  found was a shoe print and some dirt in the
  hallway. Ms. Stein wants answers.
• One of the suspects works in a bakery and the
  other is a lifeguard.

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Soil Lab

• Compare the crime lab density gradient tube
  results.
• Record your findings on the data table. Use
  descriptions such a- doesnt match or same as
  ____.
• Describe the physical characteristics of your
  soil samples.
• Record your observations in your chart.
• Examine the soil samples under a microscope.
  Place a small sample on a microscope slide
  without a cover slip.
• Record your observations in your chart.
• Use the comparisons to match the suspect to the
  crime scene.

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Density Gradient Tube Results from the Crime Lab

• Suspect 1 Suspect 2 Known 1 Known 2
  Known 3
• Crime Scene

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AFTER LAB

• Complete lab handout questions at bottom of page
  (use the back fror your answers)
• Complete HW questions for soil lab
• Due Block Day