OR/14/044 Model datasets

Terrington, R L, Shelley, C, and Ramos Cabrera, L. 2014. Model metadata report for the Leeds-Aire Valley 3D geological model. British Geological Survey Internal Report, OR/14/044.

General caveats regarding BGS datasets and interpretations are:

• 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

DTM

NextMap (Intermap) and Bald Earth (Landform Panorama) digital terrain model sub-sampled to 25 m grid spacing.

Borehole data

424 boreholes were coded by the authors using the Unlithified Deposits Coding scheme (Cooper et al., 2006)

The content code used in the BoreholeGeology database (BoGe) was ‘LE’. The ‘LE’ content code was used to extract the BLG (the down hole geology file) and BID (the borehole index file) data from the BoGe database (Figure 2). The following fields were extracted:

• QS, Number, Bsuff (Concatenated to Borehole_ID in BLG file)
• Depth to base of Unit
• Stratigraphy
• Lithology
• Interpreter
• Content Code
• Base Bed Code
• Unit Description

File:OR14044fig2.jpg

Figure 2    Borehole considered (those on cross-section) in the construction of the Leeds Aire Valley Superficial Model.

The BID file, which is the borehole index file, has no headers but contains the following columns in this order:

• Borehole_ID (Concatenation of QS, Number, Bsuff)
• Easting (In British National Grid)
• Northing (In British National Grid)
• Start Height
• Start Height Derivation (Either from the original log or automatically applied from the NextMap DTM value at the location)

Three BID files were produced in this study, a file showing all of the boreholes considered (LeedsAire_SOBI_All), those that were not used in the cross-sections (LeedsAire_SOBI_Not_Used) and those that were actually used to construct the cross-sections (LeedsAire_SOBI_Used).

Map data

• OS1:50 000 map data was used as the base topographical map
• BGS 1:10 000 DigMap GB artificial and superficial data was used for outcrop and geological unit formation (Version 2.18, released 15–01–2009)