Transfer Efficiency
Definition
The proportion of soil available at a source location that actually moves onto the receiving surface during contact. Influenced by soil moisture, contact pressure, surface roughness, and the amount of soil present. High moisture generally increases transfer but may reduce persistence.
- Definition type
- Proportion of source soil moved to a receiving surface
- Key variables
- Moisture, contact pressure, surface roughness, soil quantity
- Moisture effect
- Higher moisture usually raises transfer but lowers persistence
- Field
- Soil and sediment trace evidence
Common questions
Why does high moisture cut both ways?+
Wet soil sticks more readily on contact, raising the amount transferred, but the same moisture makes the deposit less stable afterward, so it sheds off clothing or footwear faster than a dry deposit would.
Why does transfer efficiency matter in casework?+
It helps an examiner judge whether the amount of soil recovered from a suspect is consistent with a single brief contact or points to repeated or prolonged contact with the source location.
Related terms
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- Cross-Section Sample
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- Pedogenic Heterogeneity
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- Persistence
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