OR/14/065 Model datasets

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Finlayson, A G, and Arkley, S L B. 2014. Model metadata report for the Moray Ness regional GSI3D model. British Geological Survey Internal Report, OR/14/065.

General caveats regarding BGS datasets and interpretations can be described:

  • Geological observations and interpretations are made according to the prevailing understanding of the subject at the time. The quality of such observations and interpretations may be affected by the availability of new data, by subsequent advances in knowledge, improved methods of interpretation, improved databases and modelling software, and better access to sampling locations.
  • Raw data may have been transcribed from analogue to digital format, or may have been acquired by means of automated measuring techniques. Although such processes are subjected to quality control to ensure reliability where possible, some raw data may have been processed without human intervention and may in consequence contain undetected errors.

Data location

W:\Teams\QES\QMMP\Data\MorayNessBasin_Data\Data\MorayNess-Region\RegionalModel_forGSI3d\REGIONAL_MODEL_FOR_ZOOM\GRID_EXPORTS

Digital Terrain Model (DTM) data

The DTM used for the Moray Ness Regional GSI3D model is the NEXTMap® Digital Elevation Model (exported from the BGS data portal). The DTM was originally imported at a resolution of 10 m from the data portal but problems were incurred possibly due to the large file size. The resolution was decreased to 50 m.

Data (sections)

The cross-sections were drawn as a ‘fish’ diagram with a main section through the model area and 7 cross-sections dissecting the main section at 90 degrees to it. The main section was drawn roughly following the route of the A96 road; four further sections were drawn parallel, north and south of this main cross-section, see Figure 2. An additional 14 ‘helper’ sections were drawn to aid in the construction of the GSI3D model, see Figure 3.

Figure 2 Cross-sections drawn for use in construction of the 3D model.
Figure 3 Construction of cross-sections as shown in 3D window, vertical exaggeration x 5.

Data (Boreholes)

Borehole data were entered into the BGS corporate database, BGS Borehole Geology according to the project GVS. The borehole information was extracted via the Data Portal (07/08/2009) for the model area using interpreter ‘ECAL’ and in total there were 392 boreholes and trial pits. Boreholes were generally hung according to the DTM used, however where the DTM was affected by artefacts, e.g. trees, the boreholes were aligned with the contour values.

Data (Field Information/Points)

Additional information was added to the borehole data extracted from the Data Portal, two different sources of information were collated, these being; field observation points which were collected during a period of re-surveying of sheet 84E, Nairn, see Figure 4 and Table 2, and also additional boreholes which had not been entered into the Single Onshore Borehole Index (SOBI), see Figure 4 and Table 3. Information on the deposits and thicknesses of these additional points were compiled into Excel tables and converted into ‘.bid’ and ‘.blg’ files for use in the modelling.

Figure 4 Location of boreholes (including field points and trial pits).
Table 2 Additional observation points collected during re-survey of Sheet 85E, Nairn.
Table 3 Additional boreholes not previously entered into SOBI.

Data (Geological)

The superficial polygons were taken from the DigMap digital files:

  • sc0095 Elgin and Buckie superficial
  • sc085w Knockando superficial
  • sc094e Findhorn superficial
  • sc083e Beauly superficial
  • sc084e Nairn superficial
  • sc084w Fortrose superficial
  • sc085e Glenfiddich superficial

The bedrock polygons were interpreted from recent mapping projects and the knowledge gained from the senior geologist for the area.

Data (rasters and shapefiles)

Topographic maps at 1:1 000 000 scale were extracted for the project area.