Automated mineralogical profiling of soils as an indicator of local bedrock lithology: a tool for predictive forensic geolocation

Pirrie, Duncan; Crean, Daniel E.; Pidduck, Allan J.; Nicholls, Timothy; Awbery, Roy P.; Shail, RK

doi:10.1144/sp492-2019-42

Cited by 6 publications

(4 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(20) Pirrie et al (2019) present a comprehensive systematic study of the relationship between the underlying geology and soil mineralogy in a geologically varied 3500 km 2 area of SW England. The authors applied automated mineralogical profiling of soils as an indicator of local bedrock lithology to provide a tool for predictive forensic geolocation (i.e.…”

Section: Research Developmentsmentioning

confidence: 99%

An introduction to forensic soil science and forensic geology: a synthesis

Fitzpatrick

Donnelly²

2021

View full text Add to dashboard Cite

Using forensic soil science and forensic geology as trace evidence and searches for burials is the theme of the papers in this Special Publication. The concept and design of this volume was initially established by the International Union of Geological Sciences (IUGS), Initiative on Forensic Geology (IFG), which successfully brought together forensic geologists, forensic soil scientists, police and law enforcement in the investigation of crimes. In this introductory paper a brief overview is provided of the developments in interdisciplinary knowledge exchange with use of soil and geological materials (known as “earth materials”) in the search for burials and the provision of trace evidence. The aim is to provide background information on the role and value of understanding ‘Earth materials’ ranging from the landscape scale, to the crime scene through to microscopic scale investigations to support law enforcement agencies in solving criminal, environmental, serious and organised crime, and terrorism. In this connection, recent advances in field and laboratory methods are highlighted. Finally, the 20 papers in the volume are briefly introduced and these include a diversity of global operational case studies that involve collection and analysis of Earth material from crime scenes and searches for homicide graves and other buried targets.

show abstract

Section: Research Developmentsmentioning

confidence: 99%

An introduction to forensic soil science and forensic geology: a synthesis

Fitzpatrick

Donnelly²

2021

View full text Add to dashboard Cite

show abstract

“… 25 – 27 ]. The method is a powerful and versatile tool in provenancing based on mineralogy [ 28 , 29 ] and has been successfully applied to studies on the origin of Stonehenge debitage [including the Altar Stone; 30 – 32 ].…”

Section: Petrography Of the Sarsen Coresmentioning

confidence: 99%

Petrological and geochemical characterisation of the sarsen stones at Stonehenge

et al. 2021

Self Cite

View full text Add to dashboard Cite

Little is known of the properties of the sarsen stones (or silcretes) that comprise the main architecture of Stonehenge. The only studies of rock struck from the monument date from the 19th century, while 20th century investigations have focussed on excavated debris without demonstrating a link to specific megaliths. Here, we present the first comprehensive analysis of sarsen samples taken directly from a Stonehenge megalith (Stone 58, in the centrally placed trilithon horseshoe). We apply state-of-the-art petrographic, mineralogical and geochemical techniques to two cores drilled from the stone during conservation work in 1958. Petrographic analyses demonstrate that Stone 58 is a highly indurated, grain-supported, structureless and texturally mature groundwater silcrete, comprising fine-to-medium grained quartz sand cemented by optically-continuous syntaxial quartz overgrowths. In addition to detrital quartz, trace quantities of silica-rich rock fragments, Fe-oxides/hydroxides and other minerals are present. Cathodoluminescence analyses show that the quartz cement developed as an initial <10 μm thick zone of non-luminescing quartz followed by ~16 separate quartz cement growth zones. Late-stage Fe-oxides/hydroxides and Ti-oxides line and/or infill some pores. Automated mineralogical analyses indicate that the sarsen preserves 7.2 to 9.2 area % porosity as a moderately-connected intergranular network. Geochemical data show that the sarsen is chemically pure, comprising 99.7 wt. % SiO2. The major and trace element chemistry is highly consistent within the stone, with the only magnitude variations being observed in Fe content. Non-quartz accessory minerals within the silcrete host sediments impart a trace element signature distinct from standard sedimentary and other crustal materials. 143Nd/144Nd isotope analyses suggest that these host sediments were likely derived from eroded Mesozoic rocks, and that these Mesozoic rocks incorporated much older Mesoproterozoic material. The chemistry of Stone 58 has been identified recently as representative of 50 of the 52 remaining sarsens at Stonehenge. These results are therefore representative of the main stone type used to build what is arguably the most important Late Neolithic monument in Europe.

show abstract

“…Slags, pottery, stoneware and artefacts can be studied in an archaeological context for recognition of provenance and trade routes, but also for the better understanding of their production processes [15][16][17][18]. Soil and solid particles of all kinds are objects in forensic science [19][20][21]. SEM-based Automated Mineralogy allows novel insight in the fields of process chemistry and recycling technology [22][23][24].…”

Section: Introductionmentioning

confidence: 99%

SEM-Based Automated Mineralogy and Its Application in Geo- and Material Sciences

Sandmann²,

2020

View full text Add to dashboard Cite

Scanning electron microscopy based automated mineralogy (SEM-AM) is a combined analytical tool initially designed for the characterisation of ores and mineral processing products. Measurements begin with the collection of backscattered electron (BSE) images and their handling with image analysis software routines. Subsequently, energy dispersive X-ray spectra (EDS) are gained at selected points according to the BSE image adjustments. Classification of the sample EDS spectra against a list of approved reference EDS spectra completes the measurement. Different classification algorithms and four principal SEM-AM measurement routines for point counting modal analysis, particle analysis, sparse phase search and EDS spectral mapping are offered by the relevant software providers. Application of SEM-AM requires a high-quality preparation of samples. Suitable non-evaporating and electron-beam stable epoxy resin mixtures and polishing of relief-free surfaces in particles and materials with very different hardness are the main challenges. As demonstrated by case examples in this contribution, the EDS spectral mapping methods appear to have the most promising potential for novel applications in metamorphic, igneous and sedimentary petrology, ore fingerprinting, ash particle analysis, characterisation of slags, forensic sciences, archaeometry and investigations of stoneware and ceramics. SEM-AM allows the quantification of the sizes, geometries and liberation of particles with different chemical compositions within a bulk sample and without previous phase separations. In addition, a virtual filtering of bulk particle samples by application of numerous filter criteria is possible. For a complete mineral phase identification, X-ray diffraction data should accompany the EDS chemical analysis. Many of the materials which potentially could be characterised by SEM-AM consist of amorphous and glassy phases. In such cases, the generic labelling of reference EDS spectra and their subsequent target component grouping allow SEM-AM for interesting and novel studies on many kinds of solid and particulate matter which are not feasible by other analytical methods.

show abstract

Automated mineralogical profiling of soils as an indicator of local bedrock lithology: a tool for predictive forensic geolocation

Cited by 6 publications

References 37 publications

An introduction to forensic soil science and forensic geology: a synthesis

An introduction to forensic soil science and forensic geology: a synthesis

Petrological and geochemical characterisation of the sarsen stones at Stonehenge

SEM-Based Automated Mineralogy and Its Application in Geo- and Material Sciences

Contact Info

Product

Resources

About