Anthropogenic Fraction
Definition
The human-made content of a soil sample: concrete dust, brick fragments, paint flakes, fly ash, road tar. Often the most discriminating component in an Indian urban or peri-urban sample.
- Includes
- Concrete dust, brick fragments, paint flakes, fly ash, road tar
- Origin
- Human-made or human-modified material in soil
- Value
- Often the most discriminating component in urban samples
- Field
- Forensic soil and botanical evidence comparison
Common questions
Why is the anthropogenic fraction more discriminating than the mineral fraction in a city sample?+
Natural mineral assemblages in a dense urban area can be broadly similar across many sites, while construction debris, paint chemistry and industrial particles vary block to block with local building history and land use, giving sharper site-to-site differences.
What information can a paint flake in the anthropogenic fraction provide?+
Paint layer sequence, pigment composition and binder type can be compared to a specific structure or vehicle's paint system, sometimes narrowing a soil sample's origin to a particular building or repainting event.
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