The limestone and dolomite resources of the country north and west of Ashbourne, Derbyshire : description of 1:25,000 sheet SK 15 and parts of 04, 05 and 14

The study of samples from 25 cored boreholes, 56 major sections and a large number of small exposures, together with information from the records and geological maps of the Institute, form the basis of the assessment of limestone and dolomite resources in the country lying to the north and west of Ashbourne, Derbyshire. The limestones have been classified on the basis of their calcium carbonate content, and the accompanying 1:25 000 resource map shows the distribution of the recognised categories of limestone at or near to the surface. Horizontal sections constructed from the borehole data and from knowledge of the regional geology indicate the categories likely to be encountered at depth. Three resource blocks have been outlined and for each, the geology, the categories of limestone and the occurrences of other rocks are described. The results of investigations of chemical and mechanical properties are presented with outline borehole logs and the data are statistically analysed for the stratigraphical units described

The application of 3D geological modelling to aquifer recharge assessments in an urban environment

The development of an attributed 3D model of the Quaternary deposits across 75 km2 of central Manchester and Salford is providing a basis for new types of applied (thematic) outputs. Proprietary software designed specifically for use in Quaternary sequences has been used to construct a model of the glacial and post-glacial sequences in an area now undergoing rapid regeneration. The potential of the model to deliver information relevant to a range of practical applications is illustrated by an urban groundwater case study centred on the industrial area of Trafford Park. The sensitivity of the Permo-Triassic sandstone bedrock aquifer to pollution and the extent to which recharge may occur have been analysed through detailed characterization of the underlying superficial deposits. Potential hydrogeological pathways from ground surface to the sandstone are identified, and thematic outputs show the importance of the Manchester Ship Canal and related waterways as potential sources of recharge and pollution of the bedrock aquifer. The move towards 3D modelling of the shallow subsurface provides flexibility in meeting user needs that is not available from conventional 2D geological sources. It is suggested that modelling of this type should be used by site developers and remediators to design more targeted and cost-effective site investigations and risk assessments

Archaeological and environmental investigations of Late Glacial and Holocene river valley sequences on the River Soar, at Croft, Leicestershire

The sediments, stratigraphy and archaeology of several sections through Lateglacial and Holocene deposits associated with the past course of the Thurlston Brook at Croft, Leicestershire, UK are outlined. The results of pollen, plant macrofossil and insect analyses from these deposits are presented and this information is used to provide a detailed reconstruction of changing river conditions and human land use at this location during the Holocene. Despite the presence of hiatuses in the record seen at Croft, and other sites of this scale, with accurate work and clear dating controls it is possible to 'stitch' together continuous detailed sequences. The general pattern of Holocene landscape and fluvial change appears to echo that seen in the Trent valley region and nationally. It is suggested that small headwater catchments such as at Croft have the potential to provide detailed and sensitive records of Holocene events comparable with those from 'standard' sediment sequences