Name: ________________________________________ Date: __________________ Period: _____
Vocabulary - Soil
Pg 409-414
Define the following words as they pertain to forensic science.
1. soil (for forensics) Any disintegrated surface material, natural or/and artificial
that lies on or near the Earth’s surface
2. mineral A naturally occurring solid formed through geological processess
3. density Mass
How compact soil is
Volume
4. density gradient tube Glass tube filled from bottom to top with liquids of
successively lighter densities used to determine density distribution of soil
5. pH Measure of acidity or alkalinity of a solution. Measure of H + ion
concentration
6. Conductivity measure of ability to conduct electricity. Measure of ions in a
solution due to salt and metals.
7. Clay Fine grained soil that can be hardened when dried
8. Sand Large grain rock and mineral particles
9. Silt Soil or rock between sand and clay. Medium sized particles
10. Loam The spongy top layer of soil. Made of silt and sand combined.
1. How can soil evidence be valuable even if the site of the crime has not been
ascertained?
Small amounts of soil may be found on a person or object far from the
actual site of a crime. Geologists could link to general vicinity.
2. How can minerals be important in the comparison of soil samples?
Color, geometric shape, density, refractive index (the degree to which
light bends)
Used as comparison points of soils
3. What is the most important consideration when collecting soil samples from a crime
scene? At what locations should soil standard/reference samples be collected?
Collect at various intervals within a 100 yard radius and any alibi
locations
Only the top layer is collected
Must establish variation of soil at the crime scene
4. Why is soil collected from suspect automobiles left in lump form?
In order to preserve the order in which the soil adhered to the car.
5. Naturally occurring crystals commonly found in soils are _Minerals.
6. A comparison of the density of soil particles is readily accomplished through the use of
density gradient tubes.
7. True or False: The ultimate value of soil is that evidence depends on its variation at the
crime scene.