Ground penetrating radar and electrical resistivity tomography surveys with a subsequent intrusive investigation in search for the missing Beaumont children in Adelaide, South Australia.

Jane, Arnna, and Grant Beaumont went missing from Glenelg Beach in Adelaide, South Australia on 26 January (Australia Day) 1966. Despite multiple land and sea searches over nearly 60 years, the children have not been found. New credible eyewitness testimony led to a site of interest at the now disused New Castalloy factory in North Plympton, Adelaide. This site has a complex stratigraphy of anthropogenic fill, which made ground penetrating radar (GPR) investigations unpromising. Electrical resistivity tomography (ERT), while not commonly used in a forensic capacity, provided an alternative approach that allowed suitable depth penetration to resolve a feature of interest, which was subsequently excavated by the South Australia Police. This feature did contain organic, and animal remains but, sadly, not the grave of Jane, Arnna, and Grant Beaumont. However, this investigation highlights the potential to use ERT in a forensic capacity, as well as the limitations of using geophysical techniques for covert burial detection.

The suitability of using domestic pigs (Sus spp.) as human proxies in the geophysical detection of clandestine graves.

Research in many forensic science fields commonly uses domestic pigs (Sus spp.) as proxies for human remains, due to their physiological and anatomical similarities, as well as being more readily available. Unfortunately, previous research, especially that which compares the decompositional process, has shown that pigs are not appropriate proxies for humans. To date, there has not been any published research that specifically addresses whether domestic pigs are adequate human proxies for the geophysical detection of clandestine graves. As such, the aim of this paper was to compare the geophysical responses of pig cadavers and human donor graves, in order to determine if pigs can indeed be used as adequate human proxies. To accomplish this, ground penetrating radar (GPR) and electrical resistivity tomography (ERT) responses on single and multiple pig cadaver graves were compared to single and multiple human donor graves, all of which are in known locations within the same geological environment. The results showed that under field conditions, both GPR and ERT were successful at observing human and pig burials, with no obvious differences between the detected geophysical responses. The results also showed that there were no differences in the geophysical responses of those who were clothed and unclothed. The similarity of the responses may reflect that the geophysical techniques can detect graves despite what their contents are. The study implications suggest that experimental studies in other soil and climate conditions can be easily replicated, benefiting law enforcement with missing persons cases.

A multidisciplinary approach to locating clandestine gravesites in cold cases: Combining geographic profiling, LiDAR, and near surface geophysics.

By nature, clandestine burials are difficult to locate, an issue that can complicate the legal process, and interrupt the natural grief process of the family. The purpose of this paper is to present a three-step process to search for clandestine graves using (1) geographic profiling, (2) light detection and ranging (LiDAR), and (3) near surface geophysics. Each process incrementally decreases the geographic area being searched, while increasing the level of detail provided to investigators. Using two well-known Australian cases and one experimental study, this paper will demonstrate how (1) can highlight potential search areas, (2) can further narrow down the location of potential burial sites within these search areas, and (3) can assist with locating the clandestine grave. Although each technique on its own can successfully locate graves, combining the techniques can provide the most efficient approach to locate those who are missing and buried.

Evaluating the morphological and metric sex of human crania using 3-dimensional (3D) technology.

Identifying the skeletal remains of an unidentified individual is a priority for the medico-legal system because identification increases the chances of finding the person responsible and provides closure to the family. The purpose of this research was to develop a combined morphological and metric cranial sex assessment method using 3D technology that accommodates the medico-legal system, and their use of 3D models facilitates the technological transition to digitally archived skeletal collections. A total of 91 individuals of European biogeographical ancestry from the William M. Bass Donated Skeletal Collection (University of Tennessee Knoxville) were imaged using photogrammetry, turned into 3D models using Agisoft PhotoScan, and digitally evaluated using 3D Studio Max. This novel method digitally evaluated five cranial traits, including the nasal aperture height, nasal aperture width, mastoid length, the general size and architecture, and the supraorbital ridges, combining techniques that can only be done digitally with those that can be completed on the actual bone. Preliminary statistical tests demonstrate an overall accuracy rate of 90% when tested against the training sample (20 males, 20 females) and 75% when tested against the test sample (51 individuals). Although no intra- or inter-observer error rate tests were done, and further testing on other skeletal collections is necessary, this method allows forensic anthropologists to perform relatively easy point-to-point measurements, the quantification of traditionally non-quantified traits, the possibility of reproducible results, and the ability for future analyses or research.

Geomatic techniques in forensic science: A review.

The purpose of this review paper is to highlight various geomatic techniques that crime scene reconstructionists or forensic practitioners can use to document different kinds of scenes, highlighting the advantages, disadvantages, and when best to use each technology. This paper explores geomatic techniques such as a total station, photogrammetry, laser scanners and structured light scanners and how they can be used to reconstruct crime scenes. The goal of this paper is not to discredit manual methods, as they are long standing and reliable, but instead to shed light on alternative methods that may produce equally or more accurate results with a more visually appealing final product. It is important for law enforcement and forensic professionals to understand the advantages and disadvantages of each technique, knowing when certain techniques should be used (and when they should not), and being able to revert to traditional methods if required.