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The Derbyshire Platform is a Mississippian aged flat-topped, steep sided platform that forms the westernmost expression of the Derbyshire-East Midlands Platform. On the south-east platform margin, 60 km2 of Visean limestone has been dolomitised, forming two distinct bodies. One of these bodies forms along a major NW–SE trending basement fault and smaller, associated, N–S trending faults and fractures. This study uses outcrop, petrographic and geochemical analysis to better constrain the timing and mechanism for this fault-controlled dolomitisation. Field relationships demonstrate dolomitisation was multi-phase and initiated after the main phase of matrix pore-occluding calcite cementation on the Derbyshire Platform and terminated prior to the main phase of mineralisation. Fluids are interpreted to have fluxed from adjacent basins, primarily along strike-slip crustal faults that were reactivated during basin inversion at the onset of the Variscan Orogeny. Fluid supply was episodic and progressively confined to fractures as matrix porosity became occluded. The study demonstrates the complex interplay between basin kinematics, host rock permeability and timing of fluid supply through seismic valving along faults that connect the carbonate platform to basin compartments. This ultimately controlled the position of dolomite geobodies along faults and provides a record of fluid flow during the transition from thermal subsidence to post-rift basin inversion. The findings have implications for the exploration of both minerals and hydrocarbon within dolomitised host rocks and can inform studies of fluid transfer and reaction on carbonate platforms within the burial realm. more...

Landslide susceptibility modelling in tropical climates is hindered by incomplete inventory due to rapid development and natural processes that obliterate field evidence, making validation a challenge. Susceptibility modelling was conducted in Kuala Lumpur, Malaysia using a new spatial partitioning technique for cross-validation. This involved a series of two alternating east-west linear zones, where the first zone served as the training dataset and the second zone was the test dataset, and vice versa. The results show that the susceptibility models have good compatibility with the selected landslide conditioning factors and high predictive accuracy. The model with the highest area under curve (AUC) values (SRC = 0.92, PRC = 0.90) was submitted to the City Council of Kuala Lumpur for land use planning and development control. Rainfall-induced landslides are prominent within the study area, especially during the monsoon period. An extreme rainfall event in December 2021 that triggered 122 landslides provided an opportunity to conduct retrospective validation of the model; the high predictive capability (AUC of PRC = 0.93) was reaffirmed. The findings proved that retrospective validation is vital for landslide susceptibility modelling, especially where the inventory is not of the best quality. This is to encourage wider usage and acceptance among end users, especially decision-makers in cities, to support disaster risk management in a changing climate. more...

The Brassington Formation of the Pennines is the most extensive onshore Miocene succession in the UK. It is preserved as outliers in Lower Carboniferous Limestone. During the Cenozoic, central England underwent uplift, with erosion of post-Mississippian strata from the Pennine axis in the Peak District. The Brassington Formation is hence significant in reconstructing Cenozoic geological history. It is non-marine, derived from Triassic sandstone and of Mid–Late Miocene age. The c. 60 outliers occur in three clusters over c. 220 km2. They are remnants of a sedimentary prism at least 75 m thick and with a volume of c. 10 km3. Suffosion of bedrock, conditioned by aggressive precursor fluids of hypogenic origin, was the major control on subsidence. The calculated volume of the fills in the Bees Nest and Green Clay outliers is 3.7–5.0 × 106 m3. Referenced to a sub-Miocene surface at c. 450 m OD in pre-subsidence times, the original volume of this subsidence complex was c. 21.8 × 106 m3 and the aggregated volume of the Late Neogene White Peak palaeokarst was at least 0.66 km3. Subsidence was concomitant with Pliocene uplift of the Pennine Axis, suggesting suffosion accommodation of 3 × 106 m3 per km2 or 244 m3 per annum. more...

Satellite Interferometric Synthetic Aperture Radar (InSAR), geological data and Small Unmanned Aerial Vehicle (SUAV) surveying was used to enhance our understanding of ground movement at five areas of interest in Northern Ireland. In total 68 ERS-1/2 images 1992–2000 were processed with the Small Baseline Subset (SBAS) InSAR technique to derive the baseline ground instability scenario of key areas of interest for five stakeholders: TransportNI, Northern Ireland Railways, Department for the Economy, Arup, and Belfast City Council. These stakeholders require monitoring of ground deformation across either their geotechnical infrastructure (i.e., embankments, cuttings, engineered fills and earth retaining structures) or assessment of subsidence risk as a result of abandoned mine workings, using the most efficient, cost-effective methods, with a view to minimising and managing risk to their businesses. The InSAR results provided an overview of the extent and magnitude of ground deformation for a 3000 km2 region, including the key sites of the disused salt mines in Carrickfergus, the Belfast–Bangor railway line, Throne Bend and Ligoniel Park in Belfast, Straidkilly and Garron Point along the Antrim Coast Road, plus other urbanised areas in and around Belfast. Tailored SUAV campaigns with a X8 airframe and generation of very high resolution ortho-photographs and a 3D surface model via the Structure from Motion (SfM) approach at Maiden Mount salt mine collapse in Carrickfergus in 2016 and 2017 also demonstrate the benefits of very high resolution surveying technologies to detect localised deformation and indicators of ground instability more...

Recent findings in London show that the subsurface is much more complex than expected,with a number of apparently anomalous features that present a direct hazard to infrastructure development and a risk to ground water management. Of these features, one of the least understood are the large superficial hollows which occur in the rockhead—in much of the London Basin, this is the top of the London Clay Formation—and which are infilled by a range of Quaternary deposits, principally alluvial sands and gravels deposited by the River Thames and its tributaries. The hollows range in size and shape. Several are a few hundred metres across and can be up to 40–50 m deep, though determining their exact form is problematic. The soil and sediment infill of the hollows differs substantially from the surrounding ground in terms of strength and drainage, as well as some differences in chemistry. This presents a real hazard to infrastructure as there is a potential for vertical and horizontal movement, flooding, as well as increasing the risk of contamination of the deeper aquifer. In the paper, the locations and characteristics of known hollows and deformed strata are reviewed and evidence for how they formed is reassessed, systematically considering different hypotheses (scour, ground ice, karst subsidence, seismo-tectonic). From this we consider the implications for continued development of subsurface infrastructure development, and for water resources. more...

“Sustainable development” implies that a stable relationship between human activities and the natural world is possible such that the prospects of future generations do not diminish. Can this really be achieved in our urban centres where social and economic issues are often the driving force behind development? Geoscience information has traditionally been under-utilised in planning and development, because all too often its relevance and significance is misunderstood or underappreciated. However, this is starting to change. Using case studies from London and the Thames Gateway Development Zone, this paper discusses how technological developments, such as improvements in GIS technologies and 3D modelling software, are driving this turnaround. The paper also considers the impact of organisations not sharing ground investigation geodata and know-ledge about anomalous ground conditions across London, the huge benefits that data sharing can offer and how lessons learned in this study can be applied to other urban centres. The paper will show that within the environmental ecosystem, if one component part is misunderstood, then developing sustainably without compromising future needs will be difficult, if not impossible, to achieve. In London, difficult ground conditions cost developer's time and money through project overruns and expensive engineering solutions. A more sustainable solution is in improving our understanding of the relationship between the geology (lithology) and its properties (physical, chemical or hydrological characteristics). We will show that for the urban underground to be fully utilised throughout Europe, the lack of development policies for the subsurface needs to be addressed. For a subsurface development policy to be written, stakeholders will need to regard the urban underground as environmentally sensitive, just as it does for the surface. more...

Detailed mapping, sampling and petrological analysis of a tufa deposit in the Via Gellia, above Cromford in Derbyshire, has enabled interpretation of the depositional and post-depositional history of the tufa in context of the geomorphology and hydrogeology of the area. more...

This report presents the work undertaken as part of the EO MINERS WP3 - project task 3.1. “Site Specific Available Data Collection” and develops a conceptual site model (CSM) for the Witbank coalfield, South Africa and for Bank Colliery, South Africa which has been selected to demonstrate the automated time-lapse electrical resistivity monitoring (ALERT) system of a leachate plume. The report presents the available information regarding known apparent environmental impacts. This information is derived from a literature review and from the findings of surveys conducted as part of work package WP1. Additionally the principal socio-economic impacts defined by WP1 have been presented. It goes on to consider the environmental factors that influence the transport of contaminants from the source to the exposed individuals or environmental receptors, through identified potential exposure pathways, describing the source- pathway-receptor interactions through two conceptual site models (CSMs), one for the Witbank Coal Mining region and the other for Bank Colliery. A CSM for the socio-economic impacts has also been attempted. Examining the CSM results in the identification of data gaps and information needed for a full environmental assessment of mining in Witbank and provides the rational for EO selection. Present and past coal mining in Witbank is associated with a number of environmental problems, including: acid mine drainage (AMD) derived from the oxidation of pyrite in the coal, specific contaminants including potentially harmful metals and arsenic (which occur in the mining environment and in dust associated with both the operation of the mines and the transport of the coal) and ground gases that are both naturally occurring and a consequence of self-combustion of the coal and waste dumps. A wide range of ecological and socio-economic impacts result from these impacts, including the impacts on land value and agriculture. Additional problems include ground subsidence due more...

This paper presents an overview of a British Geological Survey catchment-scale research project designed to quantify catchment-derived metal loading on surface water quality. This work is focused on the Rookhope Burn, a tributary of the River Wear in the North Pennines, UK. The river has been identified in the Water Framework Directive (WFD) River Basin Management report as being at risk of failing to achieve Good Status due to mines and minewater pressures. Although geologically relatively simple, the catchment is hydrogeologically complex in that it comprises an area of entrenched karst, characterised by Lower Carboniferous Limestone exposed in the base of valleys overlain by Namurian strata, comprising interbedded shales, sandstones and limestones, which are capped by drained blanket peat. Metal loadings in this catchment result from lead and zinc mineralization and its historic exploitation and processing, which have resulted in both point source and diffuse impacts within the catchment. There have been three main phases of research: (i) collection of hydrological and water chemistry data to enable loading and mass balance calculations to be undertaken; (ii) development of a conceptual understanding of the hydrology and hydrogeology of the catchment, and (iii) application of the hydrological understanding to more recent baseline monitoring of ecological impacts. This work has identified previously unreported mine and groundwater contributions to the catchment, which may have significant implications for the design of remedial measures in the catchment. more...

This paper reports on the comprehensive monitoring of the Rookhope Burn catchment in the Weardale valley, northern Pennines (Uk), which has been subject to lead, zinc, and fluorspar mining for over two centuries. Zinc is the major contaminant in surface waters, exceeding the Environmental Quality standard value for salmonid fish. synoptic flow monitoring and water sampling have been carried out, including both inflow and instream sampling points along the Rookhope Burn, with the purpose of tracing both point and diffuse sources of Zn throughout the catchment. The Zn load profile suggests an important role for Zn-rich groundwater contributions to the stream bed and has also established the existence of Zn sinks. Evidence from hyporheic zone sampling suggests Zn reaction or surface complexation with Mn oxide surfaces forming on stream bed sediments as a potential mechanism responsible for the observed metal attenuation. Current work is focused on testing the potential of Zn isotopes to fingerprint sources and pathways of Zn in the aquatic system. Preliminary results show significant variation in the stream water Zn isotopic signature from the headwaters to the base of the catchment. more...

Recent hydrogeological investigation of the catchment of the River Wye, Derbyshire (UK) has shown that published views of the local and regional hydrogeology lack sophistication. A conceptual model of the catchment hydrogeology has been formulated using the results of water tracing experiments, water chemistry and borehole hydrograph analyses, together with detailed consideration of bedrock lithology, geological structure and karstic process. The model highlights previously unrecognized differences in the hydrogeological behaviour of the distinct bedrock units. In conjunction with an assessment of the structural setting, the underlying stratigraphical differences assist in understanding the distribution, density and form of the springs in the catchment. A similar approach might assist understanding of the hydrogeology of other karstic aquifers. more...