Hydrogeology of Niger: Difference between revisions

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|Key Formations||Period||Lithology
|Key Formations||Period||Lithology
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!colspan="4"|Geological Environment 1
!colspan="4"|Unconsolidated Sedimentary
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|Name of formation1
|Largely alluvium and aeolian deposits
||Time period
||Quaternary
||Description
||Outcrops of Quaternary deposits occur across the country, including alluvium in river valleys, and areas of aeolian sand dunes in the more arid areas.
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!colspan="4"| Chad Basin - Sedimentary
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|Chad Formation
||Cretaceous - Quaternary
||The Chad Formation is of Quaternary age, and reaches many 100s of metres thick. It consists of unconsolidated fine to coarse grained sands and gravels with sandy clays. These are lake-margin, alluvial fan, deltaic and aeolian deposits, interbedded with lacustrine clay layers. Abrupt changes in clay and sand content are common, and the sediments usually occur as overlapping lenses.
 
The Chad Formation is underlain by Tertiary and some Cretaceous age sedimentary rocks, from loosely cemented sandstones to shales, siltstones, mudstones, ironstones, lignites and conglomerates, and coals in some places.
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!colspan="4"| Geological Environment 2
!colspan="4"| Iullemeden Basin - Sedimentary
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||Cretaceous - Tertiary
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||Equivalent to the Sokoto Basin in northwestern Nigeria. The Iullemeden Basin stretches across parts of Mali, Niger, Benin and northwest Nigeria. The sedimentary sequence is largely marine in origin, and includes sandstones, mudstones, limestones and clayey or marly limestones and shales.
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!colspan="4"| Geological Environment 3
!colspan="4"|Mesozoic to Palaeozoic Sedimentary
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||Cambrian to Cretaceous
||These sedimentary rocks include fluviatile and lacustrine clastic sandstones, marine and continental shales, and continental sandstones.
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!colspan="4"| Basement
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||Precambrian
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||Plutonic grantitic and gneissose and undifferentiated crystalline metamorphic rocks.
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Revision as of 14:06, 23 September 2015

Africa Groundwater Atlas >> Hydrogeology by country >> Hydrogeology of Niger


Most of the textual information on this page was taken from the chapter on Niger in the report ‘Groundwater in North and West Africa’ (UN 1988).

If you have more recent information on the hydrogeology of Niger, please get in touch.


Compilers

Dr Kirsty Upton and Brighid Ó Dochartaigh, British Geological Survey, UK

Geographical Setting

Map of Niger (For more information on the datasets used in the map see the geography resources section)

General

Estimated Population in 2013* 17,831,270
Rural Population (% of total) (2013)* 81.8%
Total Surface Area* 1,266,700 sq km
Agricultural Land (% of total area) (2012)* 35.4%
Capital City Niamey
Region Western Africa
Border Countries Nigeria, Benin, Burkina Faso, Mali, Algeria, Libya, Chad.
Annual Freshwater Withdrawal (2013)* 983.6 Million cubic metres
Annual Freshwater Withdrawal for Agriculture (2013)* 66.7%
Annual Freshwater Withdrawal for Domestic Use (2013)* 30.0%
Annual Freshwater Withdrawal for Industry (2013)* 3.3%
Rural Population with Access to Improved Water Source (2012)* 42.1%
Urban Population with Access to Improved Water Source (2012)* 98.7%

* Source: World Bank


Climate

Average monthly precipitation for Niger showing minimum and maximum (light blue), 25th and 75th percentile (blue), and median (dark blue) rainfall Average monthly temperature for Niger showing minimum and maximum (orange), 25th and 75th percentile (red), and median (black) temperature Quarterly precipitation over the period 1950-2012 Monthly precipitation (blue) over the period 2000-2012 compared with the long term monthly average (red)

For further detail on the climate datasets used see the climate resources section.

Surface water


Surface Water Map of Niger (For more information on the datasets used in the map see the surface water resources section)

Soil

Soil Map of Niger (For map key and more information on the datasets used in the map see the soil resources section)

Land cover

Land Cover Map of Niger (For map key and more information on the datasets used in the map see the land cover resources section)


Geology

This section provides a summary of the geology of Niger. More information is available in the report UN (1988) (see References section, below).

The geology map shows a simplified version of the geology at a national scale.


Simplified Geology of Niger (For more information on the datasets used in the map see the the Geology resources page)
Geological Environments
Key Formations Period Lithology
Unconsolidated Sedimentary
Largely alluvium and aeolian deposits Quaternary Outcrops of Quaternary deposits occur across the country, including alluvium in river valleys, and areas of aeolian sand dunes in the more arid areas.
Chad Basin - Sedimentary
Chad Formation Cretaceous - Quaternary The Chad Formation is of Quaternary age, and reaches many 100s of metres thick. It consists of unconsolidated fine to coarse grained sands and gravels with sandy clays. These are lake-margin, alluvial fan, deltaic and aeolian deposits, interbedded with lacustrine clay layers. Abrupt changes in clay and sand content are common, and the sediments usually occur as overlapping lenses.

The Chad Formation is underlain by Tertiary and some Cretaceous age sedimentary rocks, from loosely cemented sandstones to shales, siltstones, mudstones, ironstones, lignites and conglomerates, and coals in some places.

Iullemeden Basin - Sedimentary
Cretaceous - Tertiary Equivalent to the Sokoto Basin in northwestern Nigeria. The Iullemeden Basin stretches across parts of Mali, Niger, Benin and northwest Nigeria. The sedimentary sequence is largely marine in origin, and includes sandstones, mudstones, limestones and clayey or marly limestones and shales.
Mesozoic to Palaeozoic Sedimentary
Cambrian to Cretaceous These sedimentary rocks include fluviatile and lacustrine clastic sandstones, marine and continental shales, and continental sandstones.
Basement
Precambrian Plutonic grantitic and gneissose and undifferentiated crystalline metamorphic rocks.


Hydrogeology

This section provides a summary of the hydrogeology of the main aquifers in Niger. More information is available in the report UN (1988) (see References section, below).

The hydrogeology map shows a simplified version of the type and productivity of the main aquifers at a national scale (see the Aquifer properties resource page for more details).



Unconsolidated

Named Aquifers Period General Description Water quality

Sedimentary - Intergranular Flow

Named Aquifers Period General Description Water quality

Sedimentary - Intergranular & Fracture Flow

Named Aquifers Period General Description Water quality

Sedimentary - Fracture Flow

Named Aquifers Period General Description Water quality

Basement

Named Aquifers Period General Description Water quality


Groundwater Status

Groundwater quantity

Groundwater quality

Groundwater use and management

Groundwater use

Groundwater management

Groundwater monitoring

Transboundary aquifers

For further information about transboundary aquifers, please see the Transboundary aquifers resources page.

References

References with more information on the geology and hydrogeology of Niger can be accessed through the Africa Groundwater Literature Archive.

United Nations. 1988. Groundwater in North and West Africa: Niger. United Nations Department of Technical Cooperation for Development and Economic Commission for Africa.

Return to the index pages

Africa Groundwater Atlas >> Hydrogeology by country >> Hydrogeology of Niger