Searching for the IRA 'disappeared': ground-penetrating radar investigation of a churchyard burial site, Northern Ireland

A search for the body of a victim of terrorist abduction and murder was made in a graveyard on the periphery of a major conurbation in Northern Ireland. The area is politically sensitive and the case of high profile. This required non-invasive, completely non-destructive and rapid assessment of the scene. A MALA RAMAC ground-penetrating radar system was used to achieve these objectives. Unprocessed and processed 400 MHz data show the presence of a collapse feature above and around a known 1970s burial with no similar collapse above the suspect location. In the saturated, clay-rich sediments of the site, 200 MHz data offered no advantage over 400 MHz data. Unprocessed 100 MHz data shows a series of multiples in the known burial with no similar features in the suspect location. Processed 100 MHz lines defined the shape of the collapse around the known burial to 2 m depth, together with the geometry of the platform (1 m depth) the gravedigger used in the 1970s to construct the site. In addition, processed 100 MHz data showed both the dielectric contrast in and internal reflection geometry of the soil imported above the known grave. Thus the sequence, geometry, difference in infill and infill direction of the grave was reconstructed 30 years after burial. The suspect site showed no evidence of shallow or deep inhumation. Subsequently, the missing person's body was found some distance from this site, vindicating the results and interpretation from ground-penetrating radar. The acquisition, processing, collapse feature and sequence stratigraphic interpretation of the known burial and empty (suspect) burial site may be useful proxies for other, similar investigations. GPR was used to evaluate this site within 3 h of the survey commencing, using unprocessed data. An additional day of processing established that the suspect body did not reside here, which was counter to police and community intelligence.<br/

Conjunctive use of quantitative and qualitative X-ray diffraction analysis of soils and rocks for forensic analysis

This paper describes a repeatability test, comparing conventional X-ray diffraction (XRD) analyses with the technique of quantitative X-ray diffraction (QXRD) as a determinant of mineral abundance. The conjunctive use of both methods allows specific mineral abundances to be matched between scene of crime (SOC) and suspects where soil or substrate mineralogy is similar. In our test, samples from potential SOC locations were taken from car tyre tracks. A car was driven to one location by an independent person and the car submitted for sampling. The tyre-tread sample showed potential correlation to two locations: one correct and the other incorrect. QXRD showed the mineral proportions of the tyre-tread sample matched only the correct location. However, QXRD did fail to discriminate two locations that XRD did show to be different. Both methods utilise the same sample and X-ray diffractogram, suggesting that their conjunctive use, preceded by standard Earth material forensic study, is recommended

Mapping a waste disposal site using Tellus airborne geophysical data

Leakage of fluids from unregulated and/or poorly engineered waste disposal sites poses a significant direct risk to groundwater quality. Characterisation and monitoring of waste disposal sites and potentially associated groundwater contaminant plumes are generally invasive, time-consuming and expensive, particularly when the extent of the plume is unknown. This study examines the value of incorporating of Tellus and Tellus Border airborne electromagnetic (AEM) data into current assessment protocols for the characterisation and monitoring of contaminant sources and subsurface contaminant plumes. The findings demonstrate the feasibility of using airborne and ground-based non-invasive geophysical data as part of existing tiered assessment protocols for prioritising suspected sites and for guiding targeted intrusive investigations and subsequent remediation efforts

An 80-million-year sulphur isotope record of pyrite burial over the Permian–Triassic

Despite the extensive use of sulphur isotope ratios (δ34S) for understanding ancient biogeochemical cycles, many studies focus on specific time-points of interest, such as the end-Permian mass extinction (EPME). We have generated an 80 million-year Permian–Triassic δ34Sevap curve from the Staithes S-20 borehole, Yorkshire, England. The Staithes δ34Sevap record replicates the major features of the global curve, while confirming a new excursion at the Olenekian/Anisian boundary at ~ 247 million years ago. We incorporate the resultant δ34Sevap curve into a sulphur isotope box model. Our modelling approach reveals three significant pyrite burial events (i.e. PBEs) in the Triassic. In particular, it predicts a significant biogeochemical response across the EPME, resulting in a substantial increase in pyrite burial, possibly driven by Siberian Traps volcanism. Our model suggests that after ~ 10 million years pyrite burial achieves relative long-term stability until the latest Triassic

The use of geoscience methods for aquatic forensic searches

There have been few publications on the forensic search of water and fewer still on the use of geoforensic techniques when exploring aqueous environments. Here we consider what the nature of the aqueous environment is, what the forensic target(s) may be, update the geoforensic search assets we may use in light of these, and provide a search strategy that includes multiple exploration assets. Some of the good practice involved in terrestrial searches has not been applied to water to-date, water being seen as homogenous and without the complexity of solid ground: this is incorrect and a full desktop study prior to searching, with prioritized areas, is recommended. Much experimental work on the decay of human remains is focused on terrestrial surface deposition or burial, with less known about the nature of this target in water, something which is expanded upon here, in order to deploy the most appropriate geoforensic method in water-based detection. We include case studies where detecting other forensic targets have been searched for; from metal (guns, knives) to those of a nonmetallic nature, such as submerged barrels/packages of explosives, drugs, contraband and items that cause environmental pollution. A combination of the consideration of the environment, the target(s), and both modern and traditional search devices, leads to a preliminary aqueous search strategy for forensic targets. With further experimental research and criminal/humanitarian casework, this strategy will continue to evolve and improve our detection of forensic targets

A continental record of the Carnian Pluvial Episode (CPE) from the Mercia Mudstone Group (UK):palynology and climatic implications

The generally arid Late Triassic climate was interrupted by a wet phase during the mid-Carnian termed the Carnian Pluvial Episode (CPE). Quantitative palynological data from the Mercia Mudstone Group in the Wessex Basin (UK) reveal vegetation changes and palaeoclimate trends. Palynostratigraphy and bulk organic carbon isotope data allow correlation to other Carnian successions. The palynostratigraphy indicates that the Dunscombe Mudstone is Julian and the lowest part of the overlying Branscombe Mudstone Formation is Tuvalian. The Aulisporites acme characterizing the CPE in Tethyan successions and the Germanic Basin is missing in the UK. The quantitative palynological record suggests the predominance of xerophyte floral elements with a few horizons of increased hygrophytes. A humidity signal is not seen owing to the dry climate in central Pangea. Also, the signal might be masked by the overrepresentation of xerophyte regional pollen and the predominance of xerophyte hinterland flora. The bias towards regional pollen rain is enhanced by the potential increase in continental runoff related to seasonally humid conditions and differences in pollen production rates and transport mechanisms. The vegetation of British CPE successions suggests a more complex climate history during the Carnian, indicating that the CPE is not recognized by the same changes everywhere

Geomorphological signature of topographically controlled ice flow-switching at a glacier margin: Breiðamerkurjökull (Iceland) as a modern analogue for palaeo-ice sheets

Ice low-switching, which can involve changes in ice flow velocity and direction, is crucial to a full understanding of ice masses and their response to climate change. A topographically controlled ice flow switch near a glacier margin was recently documented at Breiðamerkurjökull, southeast Iceland, where the central flow unit migrated eastward in response to variations in subglacial topography and the influence of Jökulsárlón glacial lagoon. This site provides an opportunity to study the geomorphic response to ice-margin reconfiguration. Investigating contemporary processes can offer valuable insights into analogous landforms created during the deglaciation of palaeo-ice sheets. The landform assemblage and topographic setting of our Icelandic study site is compared to a palaeo-example from Alberta, Canada, which was once covered by the Laurentide ice sheet. Uncrewed aerial vehicle-(UAV) derived data was used to assess the geomorphic response to this switching and related processes across a 1.5 km2 area of the central flow unit which deglaciated between 2010 and 2023. From 2010 to 2017, the landscape featured streamlined subglacial material, a stable subglacial esker system and proglacial lakes (Landsystem A), shifting to a spillway-dominated system between 2018 and 2023 (Landsystem B). Since 2018 this section of Breiðamerkurjökull has been retreating across a reverse slope bed, resulting in the formation of quasi-annual ice-marginal spillways. Meltwater impoundment at the ice margin, formed ice-contact lakes which eventually initiated ice-margin parallel spillways draining proglacial meltwater along the local land-surface gradient, towards Jökulsárlón. As the ice retreats, an ice-contact lake forms again at the new margin and initiates the erosion of the next ice-marginal spillway. The geomorphological signature demonstrates how subglacial topography and ice-flow switching can significantly influence ice and meltwater dynamics. Since the glacier flow-switch, part of the central unit is now lake-terminating with areas of the margin evolving into a stagnant system, as it is now cut off from the accumulation centre. Therefore, Landsystem B could be analogous to regions of ice stream shut down and where ice masses retreated across reverse slope beds. For example, the Pakowki Lake region of Southeastern Alberta displays a similar landform assemblage and is presented as a palaeo-example in this work. Such insights are important for assessing the efficacy of numerical models in reconstructing the finer scale dynamics of past ice sheets during retreat