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Soil Analysis Notes

Refer to the notes on the density of glass as a review on density, physical properties, and chemical properties.

Properties of Soil

· Soil includes the disintegrated surfaces material that is found on or near the Earth's surface.
· Soil can include rocks, minerals, vegetation, animal matter, glass, paint chips, asphalt, brick, and cinders, to name a few.

How is Soil Analyzed?

· Color comparisons of dry samples under identical conditions - You want dry soil because wet soil is darker.
· Microscopic examination for debris.
· Geologically for rocks and minerals.
· Density-Gradient Tube Technique

Most density gradient tubes are composed of varying densities of ethanol and TBE (tetrabromoethane).
The particles of soil sink to the portion of the tube that has a density of equal value, and then the particles remain suspended in this 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.
The figure below shows a particle distribution pattern in a typical density-gradient tube.