|Entwisle, D C, Hobbs, P R N, Northmore, K J, Skipper*, J, Raines, M R, Self, S J, Ellison, R A, and Jones, L D. 2013. Engineering geology of British rocks and soils - Lambeth Group). British Geological Survey. (OR/13/006).|
* Geotechnical Consulting Group (GCG)
The report is the fourth of a series that examines the distribution, lithostratigraphy, lithology, engineering properties and regional variation of the geological units that are significant to engineering geology, civil engineering construction and land-use in Britain. In this volume the Lambeth Group is described by its lithological variation, mineral composition, geophysical characterisation methods, geotechnical properties and engineering behaviour.
The first section describes the geology including the deposits below and above, the named units, sequence stratigraphy and the lithological variation. The next chapter discusses the mineralogy, in particular the clay mineralogy and changes due to pedogenesis, which are illustrated with electron micrographs. Geophysical methods applicable to the Lambeth Group are described and discussed in the next section. This is followed by two sections on the geotechnical characteristics, the former describing the data acquisition, storage in the database, access and analysis and the latter the interpretation and presentation of the geotechnical data. The final chapter, on the engineering geology of the Lambeth Group, draws on the preceding chapters. A comprehensive cited reference list and bibliography are provided. The first three appendices provide extra information on the variability and distribution of the Lambeth Group and includes the type borehole, various cross-sections and an analysis of the described lithology type from borehole descriptions. The final appendix provided statistical summaries of the more commonly carried out geotechnical tests.
The lithology of different boreholes are presented as in cross-sections and as with all non-confidential boreholes held by the BGS are available, free to download (www.bgs.ac.uk/data/boreholescans/home.html). The individual items of data in the database are not attributed. The authors would like to thank all those who have contributed data to the BGS including clients, consultancies, contractors, authorities and individuals. It is hoped that this report will provide a useful sources of information to a wide range of engineers, planners, scientists and other interested parties concerned with the Lambeth Group.
It is stressed that whilst data are included in this report, these indicate the variability of the particular parameter of each unit and might be used to identify hazards or risk; they are not a substitute for an appropriate ground investigation for the project, including desk study and site investigation. This is the case for all the ‘Engineering geology of UK rocks and soils’ reports but is more important for the Lambeth Group, which is often lithologically variable.