title: Understanding Variations of Soil Mapping Units and Associated Data for Forensic Science.
abstract: Soil samples have potential to be useful in forensic investigations, but their utility may be limited due to the inherent variability of soil properties, the wide array of analytical methods, and complexity of data analysis. This study examined the differentiation of similar soils based on both gross (texture, color, mineralogy) and explicit soil properties (elemental composition, cation exchange, Fe-oxyhydroxides). Soils were collected from Fallbrook and adjacent map units from Riverside and San Diego Counties in California. Samples were characterized using multiple techniques, including chemical extracts, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy. Results were analyzed using multiple analytical approaches to compare counties and land uses. Some analyses (XRD, extractions) were better at distinguishing among samples than others (color, texture). Ratios of rare earth elements were particularly useful for distinguishing samples between counties. This potential to "fingerprint" soils illustrates the usefulness of a comprehensive soil database for criminal investigators.
authors: Department of Forensic Science, University of California Davis, 1909 Galileo Ct., Suite B, Davis, CA, 95618.|Department of Land, Air and Water Resources, University of California Davis, One Shields Ave., Davis, CA, 95616.
authors: Melissa D
authors: MD
authors: Suarez
authors: Department of Land, Air and Water Resources, University of California Davis, One Shields Ave., Davis, CA, 95616.
authors: Randal J
authors: RJ
authors: Southard
authors: Department of Land, Air and Water Resources, University of California Davis, One Shields Ave., Davis, CA, 95616.
authors: Sanjai J
authors: SJ
authors: Parikh
keywords: Fourier transform infrared spectroscopy; X-ray diffraction; forensic science; multivariant analysis; rare earth elements; soil chemistry; soil color; soil map unit