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Egalah Intrusion, Arlit, Agadez, Nigeri
Regional Level Types
Egalah IntrusionIntrusion
ArlitDepartment
AgadezRegion
NigerCountry

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Latitude & Longitude (WGS84):
18° 10' 0'' North , 8° 41' 59'' East
Latitude & Longitude (decimal):
18.16667,8.70000
GeoHash:
G#: s5npmgphs
GRN:
N13E06
Type:
Intrusion
Age:
435 ± 8 Ma
Geologic Time:
Llandovery
Dating method:
Rb-Sr whole rock
Reference for age:
Karche, J. P., & Vachette, M. (1978). Age et migration de l'activite magmatique dans les complexes paleozoiques du Niger; consequences. Bulletin de la Société géologique de France, 7(6), 941-953. doi.org/10.2113/gssgfbull.S7-XX.6.941
Köppen climate type:
BWh : Hot deserts climate
Mindat Locality ID:
408414
Long-form identifier:
mindat:1:2:408414:6
GUID (UUID V4):
0
Other/historical names associated with this locality:
Agalak


Circular intrusion 15 km in diameter composed of a central biotite granite around which is a coarse-grained amphibole-biotite granite.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


5 valid minerals.

Rock Types Recorded

Note: data is currently VERY limited. Please bear with us while we work towards adding this information!

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ 'Amphibole Supergroup'
Formula: AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ 'Feldspar Group'
ⓘ 'Feldspar Group var. Perthite'
ⓘ Fluorite
Formula: CaF2
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Quartz
Formula: SiO2
ⓘ Riebeckite
Formula: ◻[Na2][Fe2+3Fe3+2]Si8O22(OH)2
ⓘ Zircon
Formula: Zr(SiO4)

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 3 - Halides
ⓘFluorite3.AB.25CaF2
Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘQuartz4.DA.05SiO2
Group 9 - Silicates
ⓘZircon9.AD.30Zr(SiO4)
ⓘRiebeckite9.DE.25◻[Na2][Fe2+3Fe3+2]Si8O22(OH)2
Unclassified
ⓘ'Amphibole Supergroup'-AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Feldspar Group'-
ⓘ'var. Perthite'-

List of minerals for each chemical element

HHydrogen
Hⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ Riebeckite◻[Na2][Fe32+Fe23+]Si8O22(OH)2
OOxygen
Oⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ QuartzSiO2
Oⓘ Riebeckite◻[Na2][Fe32+Fe23+]Si8O22(OH)2
Oⓘ ZirconZr(SiO4)
FFluorine
Fⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Fⓘ FluoriteCaF2
NaSodium
Naⓘ Riebeckite◻[Na2][Fe32+Fe23+]Si8O22(OH)2
MgMagnesium
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
AlAluminium
Alⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
SiSilicon
Siⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ QuartzSiO2
Siⓘ Riebeckite◻[Na2][Fe32+Fe23+]Si8O22(OH)2
Siⓘ ZirconZr(SiO4)
ClChlorine
Clⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
KPotassium
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
CaCalcium
Caⓘ FluoriteCaF2
TiTitanium
Tiⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
FeIron
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ Riebeckite◻[Na2][Fe32+Fe23+]Si8O22(OH)2
ZrZirconium
Zrⓘ ZirconZr(SiO4)

Other Regions, Features and Areas containing this locality

AfricaContinent
African PlateTectonic Plate
Niger
North Africa
West AfricaUN Subregion

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

Black, R., Jaujou, M. & Pellaton, C. 1967. Notice explicative sur la carte geologique de l'Aïr à l'échelle du 1/500000. Direction des Mines et de la Geologie. Republique du Niger.
Karche, Jean-Paul, Vachette, Michelle (1978) Age et migration de l'activite magmatique dans les complexes paleozoiques du Niger. Consequences. Bulletin de la Société Géologique de France, S7-XX (6). 941-953 doi:10.2113/gssgfbull.S7-XX.6.941
Woolley, A. R. (2001) Alkaline Rocks and Carbonatites of the World, Part 3: Africa - Alkaline Rocks and Carbonatites of the World. The Geological Society of London.p.225
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