Alkaline Rocks and Carbonatites of the World

Setup during HiTech AlkCarb: an online database of alkaline rock and carbonatite occurrences

Aroyan (Orayan) And Azambaradan-Tamoelet

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Occurrence number: 
121-00-013
Country: 
Niger
Region: 
Timia
Location: 
Longitude: 8.8, Latitude: 18.1
Carbonatite: 
No

Situated between Iskou (No. 121-00-014) and Egalah (No. 121-00-012) Aroyan consists of an amphibole-biotite granite of alkali feldspar, quartz, ferrohastingsitic and arfvedsonitic amphiboles, hedenbergite and biotite. Rhyolite dykes occur in the centre of the intrusion. Igneous activity continued on the northern side of the intrusion in the form of the massif of Azambaradan-Tamoelet (Black et al., 1967) which is joined to Aroyan by dykes of microgranite. This occurrence is composed of amphibole-biotite, biotite and microcline-albite-riebeckite granites.

Age: 
A Rb-Sr whole-rock isochron gave 426±6 Ma (Karche and Vachette, 1978).
References: 

BLACK, R., JAUJOU, M. and PELLATON, C. 1967. Notice explicative sur la carte geologique de l'Air à l'échelle du 1/500 000. Direction des Mines et de la Geologie. Republique du Niger, 1-57.KARCHE, J.-P. and VACHETTE, M. 1978. Age et migration de l'activité magmatique dans les complexes paléozoïques du Niger. Consequences. Bulletin de la Société Géologique de France, 20: 941-53.

Location: 
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith