Global advancements in forensic geology
Initiative on Forensic Geology, IUGS
Although the origins and applications of geology to police and law enforcement criminal investigations has been documented since the middle part of the 19th Century, during the past few decades there have been significant advances in forensic geology (known also as ‘forensic geoscience’ or ‘geoforensics’). The objective of this presentation is to provide an overview of these recent developments.
Crime scene examination is the application of geological knowledge at crime scenes. A forensic geologist may be required to assist law enforcement at a crime scene to; collect geological samples and provide interpretations of the soil, sediment, rocks, and man-made materials.
Geological trace evidence involves the collection, analysis, interpretation, presentation and explanation of geological evidence. This evidence could become transferred onto the body, person or the clothing of a victim or offender, or onto vehicles, or other objects from and to a crime scene to help with crime reconstruction. This may also be admissible as evidence in a court to support a prosecution or defence.
Ground searches for burials are designed and implemented to locate homicide graves or items buried as part of a criminal or terrorist act. As such, searches may be protective or detective and take place in urban, rural or remote locations, on land or in water. The geoforensic search strategy (GSS), which developed over a period of 25 years provides a framework for a high assurance strategy. This is based on law enforcement search methods and an understanding of the ground and target conditions to produce a preliminary conceptual geological model. Upon which, the diggability of the ground, detectability of the target can be evaluated. This then enables the most suitable array of search assets (e.g. remote sensing, drone, geophysics, geochemistry, victim detector dogs and auguring) to be chosen. The GSS provides a proportionate, pragmatic and cost-effective method for a buried target to be detected and located, or prove (so far as is reasonable practicable) that is not present. The GSS is a blended geological and law enforcement strategies the requires effective collaboration and communication with between the forensic geologist law enforcement officer.
Crime in the minerals and mining industry occurs world-wide, in particular throughout Mexico and South America. This involves criminal and illegal mining, conflict minerals, theft of refinery and smelter products such as mineral concentrates, fraudulent activities including sample switching or adulteration to falsify assays (also known as ‘saltation’), cross border minerals smuggling and minerals fakery. These are usually controlled by illegal armed gangs, cartels and organised syndicates. Forensic geologists in collaboration with law enforcement are developing methods to deter or detect these crimes. This includes the adaptation of international guidance, elemental and mineralogical profiling, now used by some companies and governments to track and verify precious metal trading such as, gold and platinum group metals. Other techniques may include; field portable x-ray fluorescence, x-ray diffraction, conventional microscopy, automated scanning electron microscopy, the use of microtaggants and an auditable chain-of-custody.
This presentation will also provide an overview on the ongoing professionalisation of forensic geology, the establishment and progress of formal international working groups, such as the International Union of Geological Sciences (IUGS), Initiative on Forensic Geology (IFG). The need for regulation, accreditation, training and continuation of professional development within the forensic geology professional is also highlighted. Operational case examples are provided throughout with emphasis on Mexico and South America.