This complex occurs within the Prisevanskaya zone, in the central part of the Bazumsky range of the Caucasus Mountains. The Garnasar outcrops of alkaline rocks cover an area of 12 km2 and represent a subvolcanic, laccolith-like body which is confined to a system of northeast-trending faults. The rocks are alkaline syenites and trachytes in which, as seen characteristically in vertical sections, the medium- or fine-grained intrusive syenites are consistantly replaced by trachytes. The syenites are hypidiomorphic rocks with trachytic textures and vary little in composition; potassium prevails over sodium. The rocks of the effusive facies are predominantly alkaline trachytes which are commonly aphanitic but variable in composition; they have the same potassium to sodium ratio as the syenites. The main rock-forming minerals of both the syenites and trachytes are orthoclase, albite-oligolcase, stilbite, natrolite, analcime and biotite. Various types of post-volcanic alteration are manifest including zeolitization, feldspathisation, sericitization and the formation of clay minerals. The Garnasar complex is thought to be closely related to Tezhsar (No. 5).
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