Digital geological maps | at scale 1:40 000
• COMPUTERIZATION OF GEOLOGICAL MAPS OF BELGIUM AT SCALE 1:40,000
the product GIS-GEOLOGICAL MAPS OF BELGIUM (vector and raster maps)| Introduction |
The Geological Survey of Belgium (GSB) has compiled data on Belgian geology since its foundation in 1896.
Geological maps, published one century ago, at scale 1:40,000 are hosted at the GSB.
The majority of these maps (numbered from 1 to 226) was edited between 1893 and 1905 by the "Geological Commission", active during the period 1890-1919.The maps (numbered from 227 to 236), corresponding to the eastern part of Belgium, have never been published (figure 1) because the "Eastern Cantons" were not belgian at that time.
Figure 1: 226 raster maps assembled; boundaries (blue) of the three regions (Flanders, Brussels and Wallonia)(click on the image to enlarge or click here if javascript doesn't work; the image will open in a new window )
Belgium was the first country to possess such a complete and detailed geological map (In French: Boulvain F., 1993 - Un historique de la Carte géologique de Belgique - Prof. Paper, n°262, 88 pages).
Nine geological maps at scale 1:25,000 were published after the second world war by the "Geological Council" (1947-1977).
They concern the Mons basin (Prof. Marlière) and a part of the "Stavelot Massif" (Profs. Fourmarier, Asselberghs and Geukens).
| GSB and the geological cartography |
In 1989, the Flemish Region (at scale 1:50,000) and the Walloon Region (at scale 1:25,000) started the realization and the publication of new geological maps corresponding to actual needs and geological specificities of each region.
The basic sources for this revision corresponds to data collected by the GSB and stored at the GSB that are always free for consultation. In this context, the geologists from the GSB have actively participated as authors and co-authors of the new maps, or as members of the "Geological Committee" that supervised the new geological campaign.
The development of computer technologies and geographical information systems permitted a more dynamic approach during the conception of geological maps as well as the possibility of permanent data updates. The geological cartography of the Flemish Region is finished in 2003 but the cartography campaign in Wallonia will continue for years due to fieldworks and the collection of geological data during systematic campaign.
top| The geological map at scale 1:40,000: a digital product of the GSB |
Figure 2: 226 vector maps assembled;
boundaries (black rectangles) of the geological maps grid(click on the image to enlarge or click here if javascript doesn't work; the image will open in a new window )
One of the GSB missions concerns its own geological data computerization. Geological maps at scale 1:40,000 have been digitized; the rasters have been georeferenced, vectorized (figure 2) and assembled in one numerical geological map. Note that the definition of the vectorization procedure has been realized at scale 1:40,000 using a digitalisation table.
The geological map is a chronostratigraphic map and the original legend has been totally preserved. Every polygon of the vectorial map corresponds to a geological system, stage or other stratigraphical subdivisions. On the other hand, complementary information indicating local lithological variations as well as rock types (recognized by boreholes) are included on the geological maps. Each map has its own specific legend identical to that of the original document.
Digitalization is directly related to the scale 1:40,000. At a greater scale, a systematic deviation will appear between raster and vector maps. For this reason, we recommand the use of the vector maps at scale 1:40,000. It must be noted that the precision of these geological maps is linked to the cartographic projection in use during the publication of these maps at the end of the 19th century. Until today, the observed differences of the limits of similar cartographical unit between neighbouring maps has not been modified.
| Computer data |
Georeferenced and vectorized raster geological maps (version 1.2) are available for sale: for the whole country but also by packs of nine maps. This new version (1.2) includes final corrections and small bugs, a better juxtaposition between raster and vector data. The second version will be send for free to the buyers of the first version.
Raster files will be avalaible as ".tif" format with indexed colors at 150 dpi. The size of each raster file is around 3,4 MB.
Vectorial files will be available as ".tab" format for MapInfo users and ".shp" format for ArcGIS users.
| Illustrations |
Figure 3: Transparent superimposition of the geolocial map (raster) "88 Bruxelles-Saventhem" on the orthophotos - Copyright 2002 NGI. Boreholes and outcrops coming from the databank of the GSB are also figured.(click on the image to enlarge or click here if javascript doesn't work; the image will open in a new window )
Figure 4: Transparent superimposition of the vectorial geolocial map "140 Jurbise" on a topographic map (1:10,000 scale-map) - Copyright NGI. Different geological stages are identified by colors: Holocene (modern alluvium) in dark blue, the Bruxellian in yellow, the Paniselian in red, the Ypresian in mallow, the Landenian in light beige and Visean in brown.(click on the image to enlarge or click ici if javascript doesn't work; the image will open in a new window)
These products are made for universities, private consultants, public administrations that are interested to use such tools for GIS applications in territory planning for example).
The same work was done for the nine geological maps (1:25,000 scale-map) published by Marlière, Geukens, Fourmarier and Asselberghs that are digitally available for GIS applications. More details here.
| Pack prices |
You will find here the 4 packages of the product GIS-GEOLOGICAL MAPS on sale at the GSB:
- PACK (A): Price with VAT
226 digital geological maps at scale 1:40,000. Georeferenced for GIS applications (Mapinfo and ArcGis):
300 € (price for public institutions)
500 € (price for private companies)
+ shipping costs !
- PACK (B): Price with VAT
226 digital geological maps at scale 1:40,000. Georeferenced and vectorized for GIS applications:
800 € (price for public institutions)
1200 € (price for private companies)
+ shipping costs !
- PACK (C): Price with VAT
Package of nine neighbouring geological digitized and georeferenced maps:
(choice of central map by the buyer):
30 € (price for public institutions)
50 € (price for private companies)
+ shipping costs !
- PACK (D): Price with VAT
Package of nine neighbouring geological georeferenced and vectorized maps:
(choice of central map by the buyer):
80 € (price for public institutions)
120 € (price for private companies)
+ shipping costs !
| How to contact us ? |
To contact us concerning this product
Tel: +32 (0)2 788 76 38 (Dr X. Devleeschouwer)
Fax: +32 (0)2 647 73 59
Enquiries related to this product: send an e-mail!
To order
- by e-mail: Orders@naturalsciences.be
- by mail: Geological Survey of Belgium, 13 Rue Jenner, BE-1000 Brussels
