Alkaline Rocks and Carbonatites of the World

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

Umm Serih (Gheinab)

stripes

Occurrence number: 
155-00-031
Country: 
Sudan
Region: 
Bayuda Desert intrusions
Location: 
Longitude: 32.28, Latitude: 18.68
Carbonatite: 
No

This is a circular intrusion 3 km in diameter which has a 1 km diameter core of peralkaline syenite that is surrounded by three concentric shells of peralkaline syenite and peralkaline quartz syenite porphyry, the outermost being very coarsely crystalline. There are numerous radial trachyte and quartz porphyry dykes that cut both the intrusion and the country rock gneisses. There is a 50 m wide contact aureole heavily impregnated by syenite.

References: 

BARTH, H. and MEINHOLD, K.-D. 1979. Mineral prospecting in the Bayuda Desert. Part 1, Volume A. Investigation of mineral potential. Technical Report Sudanese-German Exploration Project. Hannover (Bundesanstalt fur Geowissenschaften und Rohstoffe). 336 pp. (unpublished)

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