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Unconsolidated artificial ground is an ever‐increasing feature on the Earth's surface but it poses various challenges such as pollutant release and ground instability. The process of lithification could be an important factor in changing the properties of artificial ground and ameliorating these challenges. In this study, a lithified deposit of a furnace slag associated with a former iron and steel works in Scotland was analysed to determine the mechanisms and drivers of lithification. Scanning electron microscope analysis showed that Ca leached from around the edges of clasts of slag through reaction of the chemically unstable slag with water from an adjacent water body. Dissolution of Ca (and OH−) from the slag caused the water in contact with the slag to become hyperalkaline, facilitating ingassing and hydroxylation of CO2 from the atmosphere (fingerprinted through carbon isotope analysis). Reaction of the dissolved Ca and CO2 led to precipitation of calcite. Scanning electron microscope analysis showed the calcite is distributed between slag clasts, forming rims around clasts and cementing clasts together into a solid rock‐like mass. Understanding the mechanisms and drivers of lithification in artificial ground will be important, given its widespread nature particularly in urban areas where artificial ground is the substrate of most development. [ABSTRACT FROM AUTHOR]

Zircon is a key mineral in geochemical and geochronological studies in a range of geological settings as it is mechanically and chemically robust. However, distortion of its crystal lattice can facilitate enhanced diffusion of key elements such as U and Pb. Electron backscatter diffraction (EBSD) analysis of ninety-nine zircons from the Lewisian Gneiss Complex (LGC) of northwest Scotland has revealed five zircons with lattice distortion. The distortion can take the form of gradual bending of the lattice or division of the crystal into subgrains. Zircon lattices are distorted because of either post-crystallisation plastic distortion or growth defects. Three of the five distorted zircons, along with many of the undistorted zircons in the population, were analysed by ion microprobe to measure U and Pb isotopes, Ti and REEs. Comparison of Th/U ratio, Pb/Pb age, REE profile and Ti concentration between zircons with and without lattice distortion suggests that the distortion is variably affecting the concentration of these trace elements and isotopes within single crystals, within samples and between localities. REE patterns vary heterogeneously, sometimes relatively depleted in heavy REEs or lacking a Eu anomaly. Ti-in-zircon thermometry records temperatures that were either low (~700 °C) or high (>900 °C) relative to undistorted zircons. One distorted zircon records apparent Pb/Pb isotopic ages (−3.0 to +0.3 % discordance) in the range of ~2,420-2,450 Ma but this does not correlate with any previously dated tectonothermal event in the LGC. Two other distorted zircons give discordant ages of 2,331 ± 22 and 2,266 ± 40 Ma, defining a discordia lower intercept within error of a late amphibolite-facies tectonothermal event. This illustrates that Pb may be mobilised in distorted zircons at lower metamorphic grade than in undistorted zircons. These differences in trace element abundances and isotope systematics in distorted zircons relative to undistorted zircons are generally interpreted to have been facilitated by subgrain walls. Trace elements and isotopes would have moved from undistorted lattice into these subgrain walls as their chemical potential is modified due to the presence of the dislocations which make up the subgrain wall. Subgrain walls provided pathways for chemical exchange between crystal and surroundings. Only five per cent of zircons in this population have lattice distortion suggesting it will not have a major impact on zircon geochronology studies, particularly as three of the five distorted zircons are from strongly deformed rocks not normally sampled in such studies. However, this does suggest there may be a case for EBSD analysis of zircons prior to geochemical analysis when zircons from highly deformed rocks are to be investigated. [ABSTRACT FROM AUTHOR]

Background: Patients vary widely when making decisions to consult primary care. Some present frequently with trivial illness: others delay with serious disease. Differences in health service provision may play a part in this. We aimed to explore whether and how patients' consulting intentions take account of their perceptions of health service provision. Methods: Four focus groups and 51 semi-structured interviews with 78 participants (45 to 64 years) in eight urban and rural general practices in Northeast and Southwest Scotland. We used vignettes to stimulate discussion about what to do and why. Inductive analysis identified themes and explored the influence of their perceptions of health service provision on decision-making processes. Results: Anticipated waiting times for appointments affected consulting intentions, especially when the severity of symptoms was uncertain. Strategies were used to deal with this, however: in cities, these included booking early just in case, being assertive, demanding visits, or calling out-of-hours; in rural areas, participants used relationships with primary care staff, and believed that being perceived as undemanding was advantageous. Out-of-hours, decisions to consult were influenced by opinions regarding out-of-hours services. Some preferred to attend nearby emergency departments or call 999. In rural areas, participants tended to delay until their own doctor was available, or might contact them even when not on call. Conclusion: Perceived barriers to health service access affect decisions to consult, but some patients develop strategies to get round them. Current changes in UK primary care are unlikely to reduce differences in consulting behaviour and may increase delays by some patients, especially in rural areas. [ABSTRACT FROM AUTHOR]

Background Anecdotal reports suggested that farmers were sustaining significant injuries while ear tagging newborn calves or clipping cattle prior to slaughter.Aims This national survey was designed for determining the incidence and nature of self-reported injuries to farmers that were sustained while tagging calves and clipping cattle.Methods A cross-sectional, anonymous, postal questionnaire survey was sent to all members of the National Farmers Union of Scotland with beef or dairy cattle (n = 4495).Results In total, 2439 (54%) usable questionnaires were received and 1341 injuries were reported by 591 (24%) respondents. Tagging-related injuries were reported by 297 (12%) respondents. The most commonly described injury was bruising, but lacerations (3%) and fractures (3%) also occurred. Fifty-eight (20%) individuals lost time from work, with a median of 3 days [interquartile range (IQR) = 2–7 days]. Four hundred and eighteen (17%) respondents reported clipping-related injuries. The most common injury was bruising, but lacerations (6%) and fractures (7%) also occurred. Ninety-five (23%) individuals lost time from work, with a median of 4 days (IQR = 2–14 days). Tagging injuries more commonly affected lower limbs and the trunk, while clipping injuries affected the upper limbs. Tagging injuries were associated with working alone, in an open field and with a vehicle nearby, while clipping injuries were associated with working alone, with beef cattle and with younger age. Both types of injury were associated with injuries from livestock in other circumstances.Conclusions Tagging calves and clipping cattle prior to slaughter are associated with a significant risk of injury, which may be severe, necessitating treatment and time lost from work. Policy makers, safety advisers and the farming community should reconsider whether these procedures are necessary and whether current guidelines should be modified in order to improve safety. [ABSTRACT FROM AUTHOR]

The iron and steel industry has a long tradition of bulk reuse of slags for a range of construction applications. Growing interest in recent years has seen slag resource recovery options extend to critical raw material recovery and atmospheric carbon capture. Full scale deployment of such technologies is currently limited in part by absent or partial inventories of slag deposit locations, data on composition, and volume estimates in many jurisdictions. This paper integrates a range of spatial information to compile a database of iron and steel slag deposits in mainland United Kingdom (UK) for the first time and evaluate the associated resource potential. Over 190 million tonnes of legacy iron and steel slag are present across current and former iron and steel working regions of the UK, with particular concentrations in the north west and north east of England, and central Scotland. While significant potential stockpiles of blast furnace and basic oxygen furnace slag could provide up to 0.9 million tonnes of vanadium and a cumulative carbon dioxide capture potential of 57–138 million tonnes, major management challenges for resource recovery are apparent. Over one third are located in close proximity to designated conservation areas which may limit resource recovery. Furthermore, land use analyses show that many of the sites have already been redeveloped for housing (nearly 30% urban cover). Deposits from recent decades in current or recently closed steel-working areas may have the greatest potential for resource recovery where such ambitions could be coupled with site restoration and regeneration efforts. Unlabelled Image • Iron and steel-making slags have considerable resource recovery potential. • The extent of legacy iron and steel slag deposits was previously not well quantified. • A national database of slag deposits was created and analysed for mainland UK sites. • Carbon capture potential and critical raw materials (CRM) recovery potential estimated. • Current land use and conservation designations may limit resource recovery viability. [ABSTRACT FROM AUTHOR]

The article presents an obituary for retired general practitioner Martin Forrest Brewster.

Estuaries and coastal waters are sensitive to ecological degradation but receive some of the highest levels of pollutants. One impact of these pollutants is increased greenhouse gas generation, which is significant, but difficult to estimate due to high variability and data paucity. This paper investigates key controls on methane (CH 4) and nitrous oxide (N 2 O) in the urban, mesotidal, stratified Clyde estuary, Scotland, between January 2020 and October 2022. Measurements covered the estuary longitudinally, through tidal cycles and across the river-estuary transition. Dissolved CH 4 and N 2 O were always supersaturated relative to air exhibiting strong spatial and temporal variability. Estuary surface freshwater layer CH 4 concentrations were positively correlated with turbidity and exceeded 5.4 μmol l−1. Lower saline layer CH 4 concentrations exceeded 10.8 μmol l−1 and were highest after freshwater flushing events. The CH 4 concentrations decreased exponentially with salinity persistence (time since last freshwater flushing event), reducing by 50% after 10 days of continuously saline water. Salinity persistence likely provides a tipping point between the dominance of different microbial communities. Considering the persistence of saline conditions can explain much of the previously reported variability in estuarine CH 4. In the surface freshwater layer, N 2 O exceeded 0.15 μmol l−1, while in the lower saline layer N 2 O exceeded 0.21 μmol l−1, despite lower dissolved nitrogen, increasing the N 2 O per unit available nitrogen. There was a significant inverse exponential correlation (R2 = 0.96) between N 2 O and dissolved oxygen in the lower layer, with low oxygen driving elevated N 2 O concentrations. This study provides unique insights into the conditions that generate CH 4 and N 2 O in a stratified urban-impacted estuary. [Display omitted] • CH 4 decreased exponentially with salinity persistence (50% after 10 days). • CH 4 concentrations were reinviorgated by freshwater flushing events. • Low dissolved oxygen exponentially increased N 2 O concentrations. • Nutrients, flushing and stratification all contributed to low dissolved oxygen. [ABSTRACT FROM AUTHOR]

• Urban wastewater, mine water and agricultural inputs dominated GHG generation. • Anthropogenic urban nutrient sources disproportionality increased GHGs in summer. • Low oxygen and high riverine residence time increased nutrient impacts on GHGs. • A source-to sea methodology enabled easy identification of GHG sources and sinks. • Load appointment modelling enabled separation of point and diffuse GHG sources. There is growing global concern that greenhouse gas (GHG) emissions from water bodies are increasing because of interactions between nutrient levels and climate warming. This paper investigates key land-cover, seasonal and hydrological controls of GHGs by comparison of the semi-natural, agricultural and urban environments in a detailed source-to-sea study of the River Clyde, Scotland. Riverine GHG concentrations were consistently oversaturated with respect to the atmosphere. High riverine concentrations of methane (CH 4) were primarily associated with point source inflows from urban wastewater treatment, abandoned coal mines and lakes, with CH 4 -C concentrations between 0.1 - 44 µg l−1. Concentrations of carbon dioxide (CO 2) and nitrous oxide (N 2 O) were mainly driven by nitrogen concentrations, dominated by diffuse agricultural inputs in the upper catchment and supplemented by point source inputs from urban wastewater in the lower urban catchment, with CO 2 -C concentrations between 0.1 - 2.6 mg l−1 and N 2 O-N concentrations between 0.3 - 3.4 µg l−1. A significant and disproportionate increase in all GHGs occurred in the lower urban riverine environment in the summer, compared to the semi-natural environment, where GHG concentrations were higher in winter. This increase and change in GHG seasonal patterns points to anthropogenic impacts on microbial communities. The loss of total dissolved carbon, to the estuary is approximately 48.4 ± 3.6 Gg C yr−1, with the annual inorganic carbon export approximately double that of organic carbon and four times that of CO 2, with CH 4 accounting for 0.03%, with the anthropogenic impact of disused coal mines accelerating DIC loss. The annual loss of total dissolved nitrogen to the estuary is approximately 4.03 ± 0.38 Gg N yr−1 of which N 2 O represents 0.06%. This study improves our understanding of riverine GHG generation and dynamics which can contribute to our knowledge of their release to the atmosphere. It identifies where action could support reductions in aquatic GHG generation and emission. [Display omitted] [ABSTRACT FROM AUTHOR]

• Field mapping, petrography and geochemistry presented for 4 ultramafic–mafic bodies. • Two petrogenetically distinct groups are identified. • Group 1 metaperidotites and metapyroxenites are interpreted as Archean cumulates. • Group 2 metagabbronorites most likely represent deformed Paleoproterozoic dykes. The Lewisian Gneiss Complex (LGC) is a tonalite-trondhjemite-granodiorite (TTG)-dominated fragment of the North Atlantic Craton (NAC) in northwest Scotland. End-member models describe the LGC as representing either a continuous piece of Archean crust or up to 12 geologically distinct Archean terranes, with interpretations sitting on a spectrum between these end-members. There is particular uncertainty over the correlations between the Archean–Paleoproterozoic magmatic and metamorphic events recorded by mainland part of the LGC and the part exposed on the Outer Hebridean islands of Lewis and Harris. In this paper, we present the results of field mapping, petrography, and major, trace and platinum-group element (PGE) bulk-rock geochemistry for four ultramafic–mafic bodies in Lewis and Harris, namely: Maaruig, Loch Mhorsgail, Coltraiseal Mor and Beinn a' Chuailean. We consider the effects of metamorphism and element mobility, their petrogenesis, and potential correlations with ultramafic–mafic rocks elsewhere in the LGC. Our data indicate that the studied ultramafic–mafic rocks can be subdivided into two petrologically distinct groups. Metaperidotites and metapyroxenites from Maaruig and Loch Mhorsgail are interpreted as Archean (>2.8 Ga) cumulates distinct from anything currently identified in the mainland LGC, with this interpretation based on distinctive modal layering, a discordance with surrounding TTG gneiss, fractionated PGE patterns ([Pd/Ir] N = 1.3–6.6) and negative HFSE anomalies ([Nb/La] N = 0.2–0.8). Metagabbronorites from Coltraiseal Mor and Beinn a' Chuailean, which also exhibit negative high field strength-element (HFSE) anomalies ([Nb/La] N = 0.2–0.7) and show mildly fractionated ([Pd/Ir] N = 1.2–2.8) PGE patterns, most likely represent deformed Paleoproterozoic dykes. These occurrences could be correlatives of a suite of ca. 2.4 Ga mafic dykes exposed throughout the mainland LGC (the Scourie Dykes), with the Outer Hebridean occurrences having experienced more intense Paleoproterozoic (Laxfordian) deformation/reworking. These interpretations suggest that the LGC lithologies of Lewis and Harris were proximal to the mainland LGC's Central Region by the early Paleoproterozoic but raises the possibility that they were distinct crustal blocks in the Mesoarchean. [ABSTRACT FROM AUTHOR]