OR/15/020 Modelled volume, purpose and scale

Thorpe, S. 2015. Metadata report for the Knowsley 3D geological model . British Geological Survey Internal Report, OR/15/020.

Figure 1 Modelled area (in red).

The model incorporates the town of Kirkby and the Knowsley Industrial Park located in the northwest of the project area. This industrial area lies on a sequence of superficial deposits comprising glacial, post-glacial and artificial deposits overlying the Sherwood Sandstone Group, that in places are deeply weathered to form loose sand (Price et al., 2008). The Sherwood Sandstone Group is an important source of groundwater and identifying the vulnerability of the aquifer to potential pollution from the buried sewerage network was the driver for the project. United Utilities supplied the pipeline network for foul and surface water drainage, and the EA provided new boreholes which the project incorporated into the BGS systems. Using this additional borehole data, a detailed 3D geological model of superficial and artificial deposits was created. Once the model surfaces were created, they were interrogated in a GIS against the sewerage network data. This spatial data assessment was used to highlight the relative spatial vulnerability of the underlying Sherwood Sandstone Group aquifer to potential pollution based on the thickness and distribution of permeable and weakly-permeable superficial deposits.

Figure 2 Distribution of cross-sections and geological units at outcrop viewed in GSI3D.