Catoctin/Fauquier contact

Catoctin/Fauquier contact
Power washing a quarry block near Aldie, VA that preserves a soft sediment contact of the Fauquier Formation cap carbonate and pillow basalt of the Catoctin Formation.

Tuesday, January 31, 2012

Bad-Ash Rocks: Forensic Geology Unearthed and Explained


"Every contact leaves a trace." This is the mantra repeated by forensic geologists around the globe and was first postulated by 20th century scientist Edmond Locard, director of the first crime laboratory in Lyon, France. Trace evidence is any type of material left at or taken from a crime scene, or the result of contact between two objects, such as shoes and the floor or soil.

Forensic geology applies geological principles and analytical techniques to aid in solving criminal and legal investigations. Common examples include soil evidence in provenance studies or to locate a body, determining gem or painting fraud, tracking oil spills, and much more. Although seemingly unfamiliar to most people, forensic geology is largely prevalent in the news. Recent examples include Forensic Geologist Maureen Bottrell testifying at the Casey Anthony trial. Bottrell analyzed soil material found in the trunk of Anthony's car as well as several pairs of Anthony's shoes to determine whether a link could be made between the collected sediment and possible burial site of the deceased toddler, Caylee. Other local examples include a recent string of robberies and murders over expensive shoes in the D.C. metro area.

My research follows the recent crime in our area. I will be taking several pairs of shoes, of varying tread size, and walk around selected areas; I am interested in observing the characteristics of the material that is transferred from the scene of interest to the shoe. These transferred sediments will then be compared with bulk soil samples from the area to determine if and how material is preferentially transferred based on shoe tread size. The aim of my research is to increase the efficiency and accuracy of trace evidence analysis with respect to geological materials. I am focusing on using cost-effective, practical analyses that may readily be used in laboratories across the world.

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