OR/14/057 Appendix 1

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Arkley, S L B, Finlayson, A G, and Callaghan, E A. 2014. Model metadata report for the Forres GSI3D superficial deposits model. British Geological Survey Internal Report, OR/14/057.

Data Preparation for Forres GSI3D Superficial Model

All raw data files are stored in the folder:
W:\Teams\QES\QMMP\Data\MorayNessBasin_Data\Data\MorayNess-Region\GSi3D\ForessLocalModelBaselineData

GVS file:
ForessLocalModelBaselineData\MorayNess_gvs_V9.gvs

Legend file:
ForessLocalModelBaselineData\MorayNess_legend_V3.gleg

File created and colours/textures based on Clyde modelling work.

Extra geological units were added, used on the new digital 10k superficial map of the area and checked all units in the GVS are represented in the legend file.

The BGS rgb colours were taken from new superficial map into the legend. This was achieved by opening layerfile of superficial polygons in GIS project, double click on box showing the colour of a particular unit in the key at the side, in a new window where you would change the colour of a unit click to get the pull-down menu of standard colours and then click on ‘more colours’, current rgb values will be listed here, copy rgb values into the legend file.

Bid file:
Made up of two parts: borehole information entered into SOBI (interpreter code ECAL) and field information (collected by mapping geologists and recorded in MIDAS + notes recorded from old geological field slips and maps).

  • Borehole information. This was exported from SOBI via the Data Portal (intranet) for the area to be modelled (selecting: ‘sobi-NextMap-CEH’ for start height information, ‘ECAL x3 as BOGE author and ‘all boreholes’ from BOGE) creates a .bid and a .blg file for the 492 boreholes.
  • Field information: original data held in an Excel table with 3 sheets of information (sheet 1: info from old geological field slips and maps, sheet 2: map face notes from MIDAS from mapping geologists, sheet 3: bedrock information (not relevant for this model). Sheets 1 and 2 collated into a single sheet in a new excel table. This was double checked and once approved that interpreted codes were correct these were given a map number e.g. NJ05NW to any entries that didn’t have an unique number (i.e. those with single numbers). All codes in upper case (they wouldn’t colour up in GSI3D in lower case because colours taken from legend file and all codes in upper case in there). This sheet was then split into two, separating data for a .bid file and a .blg file. Bid file requires a list of unique numbers plus x, y, z values. Only x and y values were extracted from MIDAS, z values needed to be found. Z values were generated automatically by GIS team (created 3d-shapefile of points in Arc using dtm, and exported values as a dbf file, which could then be opened in excel). Any duplicate field point entries were deleted approximately 150 field points.
  • Added i) and ii) together to make whole .bid file, path show at top of this section.

N.B. don’t have any symbols (e.g. ‘+’ or ‘,’) in file names.

Blg file:
Similar to above.

Note that need separate row for each geological unit when recording downhole information. GSI3D uses the base of each unit, so if data is recorded as a sequence of thicknesses these must be converted to depths below the top of the section.

DTM, surface grid:
ForessLocalModelBaselineData\FromDataPortal(10thJuly'09)\Forres_NEXTMAP_DTM_25m.asc

NextMap dtm; tried exporting 10 m dtm from Data Portal (Intranet), but problems downloading (probably too big a file and system couldn’t cope), Clyde project uses 25 m or 50 m resolution. So currently using 25 m resolution which imports okay. Note that the dtm extends beyond the model area in each direction, clip in GSI3D before computing volumes.

RHEM, rockhead grid:
ForessLocalModelBaselineData\FromDataPortal(10thJuly'09)\Forres_NEXTMAP_RHEM_25m.asc

As for dtm grid.

Geological linework:
ForessLocalModelBaselineData\Geological linework\From Lesley Oliver\

Morayness_supd_2d.shp + Morayness_art_2d.shp + Morayness_landf_2d.shp

Need superficial, artificial and landform polygons/linework as shapefiles

Requested from the CartoGIS office.

Note that the files need to be 2D-shapefiles not 3D-shapefiles as often received from the CartoGIS office. Usually tell if this is the problem when trying to import the file into GSI3D and you can’t see any of the attribution headings to choose ‘lexicon’.

To convert a 2D-shapefile to a 3D-shapefile software was ontained from the web, which was imported into Arc GIS project, converted and resaved.

BGS RGB colours can be seen in the GIS project if you get a layer file of the polygons from the CartoGIS office.

Project area:
ForessLocalModelBaselineData\Model area\Forres_model.shp
Shapefile exported from Arc

.Jpg’s:

  • Topographic maps

ForessLocalModelBaselineData\Topo maps\From Jenn\Forres_OS10kbw_2_(85%).jpg
ForessLocalModelBaselineData\Topo maps\From Jenn\Forres_OS25k_(90%).jpg
ForessLocalModelBaselineData\Topo maps\From Jenn\Forres_OS50k.jpg

1:10k (B&W and reduced resolution), 1:25k and 1:50k topo maps of model area were cropped to project area. General/tourist map can be downloaded through the Data Portal when extracting borehole information. N.B. all .jpg’s must have an associated world file for importing into GSI3D, in .jpgw format not .jgw as comes out automatically from Arc. Keep file size under 20 000KB where possible otherwise GSI3D becomes very slow or falls over.

  • Cross-sections

ForessLocalModelBaselineData\Pilmuir Cross Sections\Pilmuir_sections_for_GSI3D\
Use these cropped 24bit rgb rasters for GSI3D\simplified_Xsection_A_(cropped).jpg

Single image of 5 cross-sections were taken from the BGS Pilmuir report for importing into GSI3D. Sections were crop so there was a single section per image, then clipped exactly to their limits. (In GSI3Dv2.6 top right and bottom left x,y,z values need to be known. In GSI3Dv3 draw a new section line along the line of the jpg section (import a semi-transparent, georectified plan view of the section lines, jpg) then right click on section, hover over ‘raster’ and click on ‘import raster backdrop’ you need to know the z values and work out the length of the section (W)). Images must be in ‘24 bit RGB’ format not ‘32 bit CMYK’ format. All these images were converted into the correct format in Corel Photo-Paint.

  • Air photos

Not used in this model, air photos already used to compile the current geological linework.

Contour data:
W:\Teams\QES\QMMP\Data\MorayNessBasin_Data\Data\MorayNess-Region\GSi3D\ForessLocalModelBaselineData\Contours\Use these 2d-files in GSI3D

3d contour line data for the area was available as a 3D-shapefile. This was converted in Arc from a 3D-shapefile into a 2D-shapefile as was also undertaken for the geological linework.