Alkaline Rocks and Carbonatites of the World

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

Noibinskii

stripes

Occurrence number: 
136-09-005
Country: 
Russia
Region: 
Enesei
Location: 
Longitude: 92.63, Latitude: 60.33
Carbonatite: 
No

This occurrence is represented by three approximately circular bodies of quartz syenite which gradually grade into syenite. The rocks are composed of microcline, albite, quartz, biotite and barkevikite. Nepheline-bearing rocks, of which nepheline syenite porphyries are the most widely developed, are found in talus deposits. Phenocrysts (15%) are represented by feldspar, nepheline and hastingsite. The groundmass has a trachytic texture and comprises microcline (70%), nepheline (17%), aegirine (6%) and hastingsite (4%); accessories are apatite, titanite and titanomagnetite.

Age: 
K-Ar dating of nepheline syenite porphyry gave 543 Ma, peralkaline syenite porphyry 503-497 Ma and quartz syenite 453-553 Ma (Nozhkin and Trofimov, 1982).
References: 

NOZHKIN, A.D. and TROFIMOV, Yu.P. 1982. The peralkaline granite-syenite association of Srednevogovsky massif (Enisei ridge). In V.S. Sobolev (ed) Geology of coloured metal deposits from the folded margin of the Siberian Platform. 61-9. Nauka, Novosibirsk.
OSOKIN, E.D., LAPIN A.V., KAPUSTIN, Yu.L., POHVISNEVA, E.A. and ALTUHOV, E.N. 1974. Alkaline provinces of Asia. Siberian-Pacific group. In L.S. Borodin (ed) Principal provinces and formations of alkaline rocks, 91-166. Nauka, Moscow.

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