Andriyanovka

Trachybasalts are dominant at the Andriyanovka occurrence but alkali basalts, tephrites and trachyandesite-basalts are also present with occasional occurrences of absarokite and leucitite. Tuffs as well as small stock-like bodies of monzonite also occur. The tephrites contain phenocrysts of augite, diopside, plagioclase, magnetite, biotite and apatite in a matrix of plagioclase, alkali feldspar, epidote, chlorite and glass. The leucitites contain phenocrysts of augite (20-25%), magnetite, occasionally olivine, which is replaced by iddingsite, and apatite. The groundmass of the rock is composed of epileucite, aegirine and magnetite. Analyses of the rocks are given by Flerov and Koloskov (1976).