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| [[Africa Groundwater Atlas Home | Africa Groundwater Atlas]] >> [[Additional resources | Resource pages]] >> Africa Hydrogeology Maps
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| This page is in development. Please check back soon for updates.
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| ==Quantitative groundwater maps for Africa==
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| The hydrogeology maps in this Atlas are based on Africa-wide maps that were originally developed by the British Geological Survey as part of the [http://www.bgs.ac.uk/research/groundwater/international/africanGroundwater/maps.html '''Quantitative Groundwater Maps for Africa'''] project (MacDonald et al., 2010, 2012).
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| This project produced three new '''groundwater maps for Africa''', based on a [[Geology | '''geology''' map]] of Africa at 1:5 million scale (Persits et al., 2002, Furon and Lombard 1964). The three groundwater maps are:
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| ; Groundwater (aquifer) productivity
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| ; Groundwater storage
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| ; Depth to groundwater
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| These three maps can be freely downloaded in digital form as a 5 km resolution grid (xyz tab-delimited text file), which can be used in GIS. They are also available as high resolution PDF files. [http://www.bgs.ac.uk/research/groundwater/international/africangroundwater/mapsDownload.html '''Download the Africa groundwater maps here'''].
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| [[File:BGSAfricaGWMaps.jpg | center| 500px| Maps of Aquifer Productivity, Groundwater Storage and Depth to Groundwater]]
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| More information on these Africa-wide maps can be seen in these documents:
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| MacDonald, A M, Bonsor, H C, Ó Dochartaigh, B É, and Taylor, R G. 2012. [http://nora.nerc.ac.uk/id/eprint/17892/ Quantitative maps of groundwater resources in Africa]. Environmental Research Letters, 7 (2), 024009. 10.1088/1748-9326/7/2/024009
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| MacDonald, A M, Ó Dochartaigh, B É, Bonsor, H C, Davies, J, and Key, R. 2010. [http://nora.nerc.ac.uk/501779/ Developing quantitative aquifer maps for Africa]. British Geological Survey Internal Report, IR/10/103.
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| ==The hydrogeology maps in the Africa Groundwater Atlas==
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| The hydrogeology maps for each country shown in this Atlas are a further development of the Africa-wide maps described above. Information was combined to produce a single hydrogeology map that shows both '''aquifer type''' (based on the geological environment and groundwater flow/storage type) and '''aquifer productivity''' (relative aquifer productivity, or groundwater potential, from very high to very low).
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| Hydrogeology maps have been produced for each country in Africa. For some countries, the country map has been produced from the Africa-wide hydrogeology map with no further modifications. For others, further modifications have been made that better represent the hydrogeology at a national scale. These modifications were made in collaboration with the co-authors of the relevant country pages, who are experts in the hydrogeology of the respective countries.
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| Like all maps, these hydrogeology maps of Africa are a two-dimensional representation of the complex three-dimensional geological reality. They show the uppermost aquifer only. If there are other aquifers at depth, these are not shown on the maps. Also, if a major aquifer is overlain by unconsolidated sediments that don't form a major aquifer, the overlying sediments are not shown on the hydrogeology maps.
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| You can read more detail about the information shown by these maps, and how they were developed, on the [[Developing An Africa Hydrogeology Map | '''Developing the Africa Groundwater Atlas Hydrogeology Map''']] page.
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| {|
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| [[File: Hydrogeology.png | 500px|center| thumb| Africa Groundwater Atlas Hydrogeology map of Africa, 1:5 million scale]]
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| [[File: Hydrogeology_Key.png | center| thumb| Legend for Africa Groundwater Atlas hydrogeology map of Africa| 500x195px]]
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| ==Other hydrogeology maps for Africa==
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| ===[http://www.whymap.org/whymap/EN/Home/whymap_node.html WHYMAP]===
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| The World-wide Hydrogeological Mapping and Assessment Programme (WHYMAP) was launched in 2000 to provide summary information about global groundwater resources.
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| Several global and continental scale maps related to groundwater resources, groundwater basins, large aquifer systems, and transboundary aquifers are available to download (as pdf or image files) from the [https://www.whymap.org/whymap/EN/Map_Applications/map_applications_node_en.html '''WHYMAP''' website].
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| These maps include a [https://www.whymap.org/whymap/EN/Maps_Data/Additional_maps/gwrm_africa_pdf.pdf?__blob=publicationFile&v=2 '''groundwater resources map of Africa''']; and scans of '''national hydrogeological maps''' across Africa through the [https://geoviewer.bgr.de/mapapps/resources/apps/whymap/index.html?lang=en&tab=whymap_gwr WHYMIS] application. These national maps are also indexed in the [http://www.bgs.ac.uk/africagroundwateratlas/index.cfm Africa Groundwater Literature Archive].
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| |[[File:WHYMAPScreenshot.jpg|thumb| 400 px| center| The BGR [https://geoviewer.bgr.de/mapapps/resources/apps/whymap/index.html?lang=en&tab=whymap_gwr WHYMAP] viewer showing an example of a scanned national hydrogeological map available through WHYMIS]]
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| ===[http://www.brgm.eu/ BRGM]===
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| In 2008, BRGM published a [http://www.brgm.eu/projects/hydrogeological-map-of-africa '''hydrogeological map of Africa'''] at a scale of 1:10 Million, the first of its kind at this scale. The map is produced as a hard copy and in GIS form. It was developed by combining two categories of data: groundwater reservoir (or aquifer) type; and the proportion of precipitation available to recharge to aquifers. BRGM used extensive data to develop the map, which distinguishes eleven major hydrographic units.
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| {|
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| |[[File:BRGM_HGMap-Screenshot.png|thumb| 400 px| center | The BRGM [http://www.brgm.eu/project/hydrogeological-map-of-africa hydrogeological map of Africa]]]
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| ===[https://www.bgs.ac.uk/africaGroundwaterAtlas/atlas.cfc?method=ViewDetails&id=AGLA500854 International Hydrogeological Map of Africa]===
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| This map, at 1:5 Million scale, is not available digitally but is described in the report by Gilbrich and Struckmeier (2014).
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| Gilbrich, W H, and Struckmeier, W F. 2014. [http://unesdoc.unesco.org/images/0023/002310/231066e.pdf 50 Years of Hydro(geo)logical Mapping Activities]. German Federal Institute for Geosciences and Natural Resources (BGR) and UNESCO International Hydrological Programme (UNESCO-IHP).
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| [[Africa Groundwater Atlas Home | Africa Groundwater Atlas]] >> [[Additional resources | Additional resources]] >> Hydrogeology Map
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| [[Category:Additional resources]]
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| [[Category:Africa Groundwater Atlas]]
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