The 2020 national seismic hazard model for the United Kingdom

We present updated seismic hazard maps for the United Kingdom (UK) intended for use with the National Annex for the revised edition of Eurocode 8. The last national maps for the UK were produced by Musson and Sargeant (Eurocode 8 seismic hazard zoning maps for the UK. British Geological Survey Report CR/07/125, United Kingdom, 2007). The updated model uses an up-to-date earthquake catalogue for the British Isles, for which the completeness periods have been reassessed, and a modified source model. The hazard model also incorporates some advances in ground motion modelling since 2007, including host-to-target adjustments for the ground motion models selected in the logic tree. For the first time, the new maps are provided for not only peak ground acceleration (PGA) but also spectral acceleration at 0.2 s (SA0.2s) and 1.0 s for 5% damping on rock (time-averaged shear wave velocity for the top 30 m Vs30 ≥ 800 m/s) and four return periods, including 475 and 2475 years. The hazard in most of the UK is generally low and increases slightly in North Wales, the England–Wales border region, and western Scotland. A similar spatial variation is observed for PGA and SA0.2s but the effects are more pronounced for SA0.2s. Hazard curves, uniform hazard spectra, and disaggregation analysis are calculated for selected sites. The new hazard maps are compared with the previous 2007 national maps and the 2013 European hazard maps (Woessner et al. in Bull Earthq Eng 13:3553–3596, 2015). There is a slight increase in PGA from the 2007 maps to this work; whereas the hazard in the updated maps is lower than indicated by the European maps.

A spatial analysis of lime resources and their potential for improving soil magnesium concentrations and pH in grassland areas of England and Wales

Magnesium (Mg) is essential for animal health. Low Mg status (hypomagnesaemia) can be potentially fatal in ruminants, like cattle and sheep, and is widespread in Europe with economic impacts on farming. The application of Mg-rich agricultural lime products can help to ensure pasture forage consumed by animals contains sufficient Mg and, in areas of low pH, has the dual benefit of reducing soil acidity to levels best suited for grass production. This aim of this study was to determine if Mg-rich lime products could be used in a more effective manner in agricultural production systems. Potential resources of carbonate rocks (limestone, dolostone and chalk) in the UK, and their Mg:Ca status were identified, using datasets from the British Geological Survey (BGS). These data were combined with the locations of agricultural lime quarries, and areas where soils are likely to be deficient in Mg and/or require liming. Areas of potential demand for Mg-rich agricultural lime include areas in south east Wales, the Midlands and North East England. Although, areas where this may be an effective solution to low soil Mg values are restricted by the availability of suitable products. Conversely, areas of low soil pH in England and Wales are often found close to quarries with the ability to supply high Ca limes, suggesting that the low rates of lime use and liming is not due to supply factors. This study provides information that can help to guide on-farm decision making for use of Mg-rich and other lime resources. This could be used in conjunction with other options to reduce risks of Mg deficiency in livestock, and improve soil pH.

A Spatial Analysis of Lime Resources and their Potential for Improving Soil Magnesium Concentrations and pH in Grassland Areas of England and Wales

Magnesium (Mg) is essential for animal health. Low Mg status (hypomagnesaemia) can be potentially fatal in ruminants, like cattle and sheep, and is widespread in Europe with economic impacts on farming. The application of Mg-rich agricultural lime products can help to ensure pasture forage consumed by animals contains sufficient Mg and, in areas of low pH, has the dual benefit of reducing soil acidity to levels best suited for grass production. This aim of this study was to determine if Mg-rich lime products could be used in a more effective manner in agricultural production systems. Potential resources of carbonate rocks (limestone, dolostone and chalk) in the UK, and their Mg:Ca status were identified, using datasets from the British Geological Survey (BGS). These data were combined with the locations of agricultural lime quarries, and areas where soils are likely to be deficient in Mg and/or require liming.Areas of potential demand for Mg-rich agricultural lime include areas in south east Wales, the Midlands and North East England. Although, areas where this may be an effective solution to low soil Mg values are restricted by the availability of suitable products. Conversely, areas of low soil pH in England and Wales are often found close to quarries with the ability to supply high Ca limes, suggesting that the low rates of lime use and liming is not due to supply factors.This study provides information that can help to guide on-farm decision making for use of Mg-rich and other lime resources. This could be used in conjunction with other options to reduce risks of Mg deficiency in livestock, and improve soil pH.

The stratigraphy of the Kimmeridge Clay Formation (Jurassic) of the Vale of Pickering, Yorkshire, UK

The Upper Jurassic Kimmeridge Clay Formation (KCF) underlies much of the Vale of Pickering where it is almost wholly concealed by the Cretaceous Speeton Clay and Quaternary deposits. There are few KCF inland or coastal exposures in Yorkshire with the result that the succession was stratigraphically poorly known until the 1970s oil crisis when the British Geological Survey (BGS) drilled continuously-cored boreholes at Marton and Reighton to examine the formation as a possible source of hydrocarbons. These were supplemented in 1987 by continuously-cored boreholes drilled at Marton, Reighton, Ebberston and Flixborough by the Institut Français du Pétrole (IFP) for hydrocarbons research. Taken together, the boreholes have enabled the lithological, palaeontological, geochemical and geophysical characters of the full thickness of the formation to be examined. Comparison of the KCF successions proved in Yorkshire with those in the adjacent North Sea, the East Midlands and the Dorset coast type area, shows marked variations in thickness related to penecontemporaneous faulting. However, there are only minor variations in the lithologies and faunas at any particular stratigraphical level. This appears to be due to a combination of Milankovitch-driven climatic fluctuations and pulsed variations in sea level which combined to produce similar depositional conditions throughout the English KCF at any one time. The chronostratigraphical classification of the KCF developed in southern England has therefore been shown to be applicable to the Yorkshire outcrop and the southern North Sea. The changes in sea level may be eustatic rather than regional events, but there is insufficient paleontological evidence to enable them to be correlated with confidence with those of the standard Jurassic sea-level curve.

Raspberry Shake Instruments Provide Initial Ground-Motion Assessment of the Induced Seismicity at the United Downs Deep Geothermal Power Project in Cornwall, United Kingdom

Raspberry Shake (RS) seismographs offer the potential for affordable and citizen-led seismic monitoring in areas with few publicly available seismometers, especially in previously quiescent regions experiencing induced seismicity. However, their scientific and regulatory potential remains largely untested. We examine the ground motions recorded by 11 RS and one broadband station within 15 km of the United Downs Deep Geothermal Power (UDDGP) project in Cornwall, United Kingdom, to evaluate the RS network’s suitability to provide an initial ground-motion assessment of the region. To date, the British Geological Survey (BGS) has reported 232 induced events originating at UDDGP since flow testing began in summer 2020, with two events exceeding local magnitude (ML) 1.5. Although the RS accelerometers are too noisy for UDDGP’s microseismic events, the vertical geophones are useful. Peak ground velocity observations are consistent with relevant ground-motion models, whereas peak ground acceleration (PGA) values are greater than predicted. Regional trends in the PGA levels are likely caused by path effects. Finally, RS estimates of ML are similar to those reported by the BGS. For sparse national seismic networks, RS stations can enable a preliminary evaluation of seismic events and their ground motions.

Development of a Seabed Geomorphology classification approach; aspiring towards a robust tool to support comprehensive and consistent seabed mapping

<p>In 2016, through a collaboration between marine mapping programmes in Norway, Ireland, and the UK, we published a new classification scheme to aid the characterisation of seabed geomorphology (Dove et al., 2016). The classification scheme was developed to address shared objectives and challenges in seabed mapping, particularly to enable more consistent classification where required. The novel aspect of this framework was the effort to independently describe seabed features according to their observed physical 1-Morphology, and the more subjective interpretation of their origin and evolution (2-Geomorphology). Initial application of the approach within our own groups and externally proved promising, and through the welcome involvement of colleagues from Geoscience Australia, we continued to progress and improve the approach.</p><p>We are now within the second phase of the project, which involves the development of glossaries for both parts of the classification scheme. The glossary for part-1 Morphology was recently completed and published (Dove et al., 2020). This glossary includes a revised list of feature names, with definitions and representative diagrams for each feature. Feature definitions are in-part drawn from the International Hydrographic Organization (IHO) guide for undersea feature names, which were modified and augmented with additional terms to ensure the final feature catalogue and glossary encompasses the diversity of morphologies observed at the seabed.</p><p>Part-2 Geomorphology glossary is now in development. We anticipate it to be more complicated than the Morphology glossary due to the (often) variable meaning of different terms between different fields and individual scientists. But as for Part 1, our primary objective is to produce a useful and robust framework (applicable from the coastal zone to the abyss), that minimises duplication and/or ambiguity as much as possible. The Geomorphology glossary will include example bathymetry images to add further value.</p><p>Dove, D., Bradwell, T., Carter, G., Cotterill, C., Gafeira Goncalves, J., Green, S., Krabbendam, M., Mellett, C., Stevenson, A., Stewart, H. and Westhead, K., Scott, G., Guinan, J., Judge, M., Monteys, X., Elvenes, S., Maeten, N., Dolan, M., Thorsnes, T., Bjarnadottir, L., Ottesen, D., 2016. Seabed geomorphology: a two-part classification system. British Geological Survey, Open Report OR/16/001.</p><p>Dove, D., Nanson, R., Bjarnadóttir, L.R., Guinan, J., Gafeira, J., Post, A., Dolan, M.F.J., Stewart, H., Arosio, R. and Scott, G., 2020. A two-part seabed geomorphology classification scheme:(v. 2). Part 1: morphology features glossary.</p>

The Geological Index of the Scottish Caledonides northwest of the Highland Boundary Fault

<p>The quantification and mapping of geodiversity have gained more interest in recent years due to practical application in natural resource management and conservation. The Geological Index (I<sub>Geo</sub>) represents the quantitative expression of geological features and is part of a broader Geodiversity Index (I<sub>Geodiv</sub>), which also includes geomorphological, pedological, paleontological and hydrological elements.</p><p>In Scotland, the area delimited by the Moine Thrust Zone to the northwest and the Highland Boundary Fault to the southeast represents a fragment of the Caledonian orogenic belt that extends across parts of North America, Greenland and Scandinavia. It includes the Highlands, most of the Inner Hebrides and the islands of Orkney and Shetland. The area is underlain by two tectonic blocks – the Northern Highlands Terrane and the Grampian Terrane – separated by a major strike-slip fault, the Great Glen. Both blocks consist of an Archaean-Paleoproterozoic basement covered by the Neoproterozoic metamorphic suites of the Moine and Dalradian Supergroups, together with a series of magmatic intrusions and other rocks of late Precambrian and Phanerozoic age.</p><p>The I<sub>Geo</sub> was obtained from lithostratigraphic and lithodemic units, mapped at group and suite/complex level respectively, major geologic contacts and faults and minor igneous intrusions from the British Geological Survey 1:625k digital datasets. These were reclassified and analyzed using QGIS and ArcGIS software.</p><p>The results show overall medium and high values of I<sub>Geo</sub>, with regional variations and well-individualized areas of very high and very low values. Conspicuous transitions between extremes are observed at the north and south edges of the study area.</p><p>High I<sub>Geo</sub> values occur in five major areas across the mainland: 1). on the north coast, which exhibits small outcrops of varied lithologies; 2). in the northeast Grampian Mountains, where the deformed Dalradian rocks are intruded by the Cairngorms suite of the Newer Granites; 3). along the Great Glen, the meeting place of adjacent tectonic blocks; 4). in the Firth of Lorne area and further inland, where Neoproterozoic and Paleozoic rocks come into contact with more recent Cenozoic rocks of the Hebridean Province; 5). at the southern tip of the Kintyre Peninsula that contains isolated exposures of rocks characteristic of the nearby Midland Valley.</p><p>Low I<sub>Geo</sub> values are encountered in three major areas of the mainland: 1). southeast of the Moine Thrust Zone, an area occupied by the oldest Moine group; 2). in the Pentland Firth area that consists of the Old Red Sandstone Supergroup; 3). in the Firth of Clyde area and further inland, around the main outcrop of the youngest Dalradian group.</p><p>Offshore, the islands of Orkney and Shetland have I<sub>Geo</sub> values at opposite ends of the spectrum. The first are made up of a monotonous sedimentary cover. The latter comprise a mosaic of rocks of Precambrian and early Phanerozoic age.</p>

Landscapes of the Mind

<p>Landscapes of the Mind</p><p>Anna Hicks<sup>1</sup></p><p>Carol Cotterill<sup>2, 1</sup></p><p>Nicole Archer<sup>1, 3</sup></p><p> </p><p><sup>1</sup>British Geological Survey, Edinburgh, UK</p><p><sup>2</sup>Columbia University, New York, USA</p><p><sup>3</sup>Queen Margaret University, Edinburgh, UK</p><p> </p><p>What comes to mind when you think of landscape? Do you imagine sweeping mountain vistas and picturesque scenery? Or perhaps a bustling urban scene simultaneously concealing and revealing its present and historical narratives? Of course, both are logical, as would be any number of visualisations in between. The landscapes we inhabit are constantly recording both man-made and natural changes occurring in it, and on it, and so on us.</p><p>Therefore, our beliefs and emotions framing our worldview are shaped by landscape in many ways, and so play a powerful role in making decisions and judgements about how a landscape should be used. Creative expression through art and narrative can influence decision-making by bringing those emotional responses to a landscape to the fore.</p><p>In this paper, we share our experiences to date from collaborations through the AHRC-funded network “Landscapes of the Mind”. The network aims to develop understanding and communication of landscape challenges in Scotland, with a view to informing decision making about landscape change. Network participants are from diverse backgrounds: musicians to metalworkers, archaeologists to anthropologists; our commonality is in how we bear witness to the evolution of Scotland's landscape from our different perspectives, particularly the balance between landscape conservation and adaptation to changing culture, communities and societal needs.</p><p>The network was established shortly before the onset of the COVID-19 crisis so network participants, many of whom are new to working together, are exploring how the virtual space can influence and bolster the process of interdisciplinarity in-action, and bring new insights to the fore. Our attempt to flourish under current conditions has seen us adapt the visual-matrix - a psycho-social method with arts-practice - to the virtual space. This adapted approach brings together participants to engage in creative expressions online; expressions created by participants in relation to a particular theme. The creations, from photos, to poetry, to music, build the frame for the matrix, and act as a stimulus for participants to bring their associations to the material. </p><p>We will report on the findings from the first two matrices on Landscape and Water, and Landscape and Time, showing how the methodology allowed us to explore fluidity and place, time and space, as well as the benefits and challenges of communicating thoughts through digital means.</p><p> </p>

Artful-Geoscience: Co-Creating Urban Subsurface Futures? A discussion and an invitation.

<p>The urban subsurface is key to developing sustainable urban futures (SDG 11). Yet, as is well acknowledged, geoscientists face many challenges in engaging stakeholders and communities with the urban subsurface, as well as the challenges associated wtih fragmented data sources, knowledge gaps, citizen ‘oversight,’ and challenging subsurface cultural associations (Bricker et al. 2017, 2019). In this paper we present a case for the value of the intersections between geoscience and creative practices (from visual methods to participatory arts) in helping to address some of these challenges. To make our case we present preliminary findings from a collaboration between geoscientists and science communicators based at the British Geological Survey, and a cultural geographer experienced in researching and creating art-science collaborations. We explore three things:</p><p>We close our discussion with an invitation to join us in forming a network exploring the potential of art-geoscience collaborations for understanding, using and preserving the urban subsurface. </p>

Exploring forecast variability during volcanic ash cloud events

<p>Atmospheric transport and dispersion models are used by Volcanic Ash Advisory Centers (VAACs) to provide timely information on volcanic ash clouds to mitigate the risk of aircraft encounters. Inaccuracies in dispersion model forecasts can occur due to the uncertainties associated with source terms, meteorological data and model parametrizations. Real-time validation of model forecasts against observations is therefore essential to ensure their reliability. Forecasts can also benefit from comparison to model output from other groups; through understanding how different modelling approaches, variations in model setups, model physics, and driving meteorological data, impact the predicted extent and concentration of ash. The Met Office, the National Centre for Atmospheric Science (NCAS) and the British Geological Survey (BGS) are working together to consider how we might compare data (both qualitatively and quantitatively) from the atmospheric dispersion models NAME, FALL3D and HYSPLIT, using meteorological data from the Met Office Unified Model and the NOAA Global Forecast System (providing an effective multi-model ensemble). Results from the model inter-comparison will be used to provide advice to the London VAAC to aid forecasting decisions in near real time during a volcanic ash cloud event. In order to facilitate this comparison, we developed a Python package (ash-model-plotting) to read outputs from the different models into a consistent structure. Here we present our framework for generating comparable plots across the different partners, with a focus on total column mass loading products. These are directly comparable to satellite data retrievals and therefore important for model validation. We also present outcomes from a recent modelling exercise and discuss next steps for further improving our forecast validation.</p>