Geology, forensic

Gamma spectrometry on irradiated samples can be performed to demonstrate the process for identification of radioisotopes using the photopeaks in the spectrum. The discussion should include the applications of this technique to identify radioisotopes in various types of samples (e.g., atmospheric, geological, forensic.)... 

Apart from the well-known journals covering aspects of chemistry, physics, biology, medicine, geology, environmental science, electrical engineering, and forensic science, which all have occasional articles that use mass spectrometry for analytical purposes, the following journals frequently contain papers in which mass spectrometry plays a major role ... 

Thermal neutron activation analysis has been used for archeological samples, such as amber, coins, ceramics, and glass biological samples and forensic samples (see Forensic chemistry) as weU as human tissues, including bile, blood, bone, teeth, and urine laboratory animals geological samples, such as meteorites and ores and a variety of industrial products (166). 

In addition to the aforementioned methods, TLC in combination with other instrumental techniques have also been used for quantification of inorganic species. For example, two-dimensional TLC coupled with HPLC has been utilized for the separation and quantification of REEs in nuclear fuel fission products using silaiuzed silica gel as layer material [60]. In another interesting method, REEs in geological samples have been determined by ICP-AAS after their preconcentration by TLC on Fixion plates [32]. TLC in combination with neutron activation has been used to determine REE in rock samples on Eixion 50 x 8 layers with the sensitivity limit of 0.5 to 10 pg/g for 10- to 30-mg samples [41]. A combination of TLC and A AS has been utilized for the isolation and determination of zinc in forensic samples [27]. 

The scope of this branch of chemistry encompasses both the fundamental understanding of how to measure properties and amounts of chemicals, and the practical understanding of how to implement such measurements, including the design of the necessary instruments. The need for analytical measurements arises in all research disciplines, industrial sectors, and human activities that entail the need to know not only the identities and amounts of chemical components in a mixture, but also how they are distributed in space and time. These sectors of need include research in specific disciplines (such as chemistry, physics, materials science, geology, archeology, medicine, pharmacy, and dentistry) and in interdisciplinary areas (such as forensic, atmospheric, and environmental sciences), as well as the needs of government policy, space exploration, and commerce. 

It is a common misconception that opinions and interpretations are only offered by forensic scientists and Public Analysts. Analysts from many areas are required to provide this service, e.g. those dealing with consumer safety, geology/geochemistry, oil exploration and food science, to mention but a few. Some examples are given below. 

In recent years, Raman spectroscopy has undergone a major transformation from a specialist laboratory technique to a practical analytical tool. This change was driven on several parallel fronts by dramatic advances in laser instrumentation, detectors, spectrometers, and optical filter technology. This resulted in the advent of a new generation of compact and robust Raman instruments with improved sensitivity and flexibility. These devices could be operated for the first time by non-specialists outside the laboratory environment. Indeed, Raman spectroscopy is now found in the chemical and pharmaceutical industries for process control and has very recently been introduced into hospitals. Handheld instruments are used in forensic and other security applications and battery-operated versions for field use are found in environmental and geological studies. 

Murray, R. and Tedrow, J. C. F. (1975 [1986]). Forensic Geology Earth Sciences and Criminal Investigation. New York Rutgers University Press. 

Murray, R. C. (2004) Evidence from the Earth Forensic Geology and Criminal Investigation. Missoula, MT Mountain Press Publishing. 

Rendle, D. F. (2004). Database use in forensic analysis. Crystallogr. Rev. 10,23-28. Ruffell, A. and McKinley, J. (2004). Forensic geoscience Applications of geology, geomorphology and geophysics to criminal investigations. Earth-Sci. Rev. 69, 235-247. 

Cameron, N. G. (2004). The use of diatom analysis in forensic geoscience, in Forensic Geoscience Principles, Techniques and Applications (K. Pye and D. J. Croft, Eds.). London Geological Society Special Publication 232,277-280. 

Lombardi, G. (1999). The contribution of forensic geology and other trace evidence analysis to the investigation of the killing of Italian Prime Minister Aldo Moro. J. Forensic Sci. 44, 634-642. 

Murray, R. C. (2000). Devil in the details The science of forensic geology. Geotimes 45, 14-17. 

---