Geoforensic Location Indicator
Definition
A combination of particle types on clothing or in a vehicle whose presence or proportions narrow the possible locations where the person or vehicle has been; the strength of the inference depends on how distinctive the assemblage is relative to background variation across the region.
- Evidence type
- Particle assemblage on clothing or in a vehicle
- Basis
- Presence and proportion of particle types
- Strength depends on
- Distinctiveness versus regional background
- Related field
- Dust and airborne mineral particle analysis
Common questions
Why does the strength of this kind of indicator vary so much between cases?+
An assemblage found in an area with unusual particle combinations gives a strong, specific inference, while one dominated by common regional dust gives only weak or non-specific information.
What kinds of particles typically contribute to the assemblage?+
Mineral grains, plant material such as pollen or spores, industrial or occupational dust, and man-made fibers or debris can all combine into a characteristic assemblage.
Does this kind of indicator pinpoint an exact place a person visited?+
No, it narrows the range of plausible locations by comparing the assemblage to regional background variation, but does not pinpoint a single exact site without corroborating evidence.
Related terms
- Asbestos
- A group of naturally occurring fibrous silicate minerals: chrysotile (serpentine) and the regulated amphiboles (crocidolite, amosite, tremolite, actinolite, anthophyllite). Defined analytically as...
- Fly Ash
- Spherical or hollow glass particles collected from flue gas during coal combustion; dominated by Si-Al-Fe chemistry with trace-element profiles reflecting the coal...
- Manufactured Mineral Fibre (MMF)
- Man-made fibrous materials (glass wool, rock wool, ceramic fibre) used as insulation; resembles asbestos morphologically but has different elemental composition (no iron...
- Phase Contrast Optical Microscopy (PCOM)
- The WHO-recommended routine method for counting airborne asbestos fibres in occupational and environmental samples; counts fibres visible at 400-500x magnification, with confirmation...
- SEM-EDX
- Scanning electron microscopy with energy-dispersive X-ray spectroscopy. The electron beam excites characteristic X-rays from each element present in the target grain, giving...