stripes
The intrusion is located near the River Fad'yu-Kuda and is a curved, lens-shaped body which extends along a zone of faulting for 2 km and has a width of from 400 to 650 m. The area of the intrusion is 1 km2 and it is stock-like in form. It is composed of nepheline syenites of varying grain size but coarse- and medium-grained varieties are predominant. The principal mineralogy is nepheline, albite, microcline and aegirine with accessory melanite, titanite, apatite, zircon, rutile, sphalerite, magnetite and fluorite. Autometasomatic processes were extensive and caused the development of albite and cancrinite in the nepheline syenites.
RAVICH, M.G. and CHAIKA, L.A. 1959. Small intrusions of the Birranga shield. Trudy Nauchno-Issledovatel'skogo Instituta Geologii Arktiki, Leningrad, 88: 1-149.
