Phosphate Survey
Definition
A geochemical search method that measures soil phosphate concentration at regular sample points. Decomposing organic matter, including human remains, raises local phosphate concentrations. A phosphate anomaly in otherwise low-background soil is consistent with organic deposition but is not specific to human remains.
- Method type
- Geochemical soil search technique
- Measured variable
- Soil phosphate concentration
- Positive indicator
- Anomaly above local background level
- Specificity
- Consistent with organic decomposition, not specific to humans
Common questions
Why can't a phosphate anomaly confirm a clandestine human burial by itself?+
Elevated phosphate can come from animal carcasses, fertiliser use, septic discharge, or other organic matter, so a survey narrows a search area rather than proving human remains are present at a given anomaly.
How is a phosphate survey typically used within a wider search strategy?+
It is usually combined with other remote sensing or ground methods, such as ground-penetrating radar or cadaver-dog searches, so an anomaly flagged by phosphate testing gets targeted follow-up rather than excavation on its own.
What determines whether a phosphate reading counts as an anomaly?+
The survey establishes a local background level from unaffected control samples first, and only concentrations clearly elevated above that established baseline are treated as anomalies worth investigating further.
Related terms
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- Chain of Custody
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- Ground-Penetrating Radar (GPR)
- A geophysical method that transmits electromagnetic pulses into soil and records reflections from subsurface discontinuities. In forensic burial detection, it identifies the...
- Photogrammetry
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- Primary Burial
- A burial in which remains were placed at the recovery location at or shortly after the time of death, and decomposed in...
- Secondary Deposition
- A burial or scatter in which remains were moved from the original death location after some decomposition, then deposited at the recovery...
- Sieve Mesh Recovery
- The recovery of small bones, fragments, and associated material by passing grave fill through wire mesh of 6 mm and 2 mm...
- Total-Station Survey
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