Vol 104

The name of Academician A.N. Zavaritsky, one of the greatest scientists of our country, is associated with a significant stage in the development of Soviet petrography and geology of ore deposits.

In the works that address the problems of litho- and ore genesis, the significance of the phenomena of recrystallization is assessed in a variety of ways. Moreover, the very essence of these phenomena is interpreted differently, so it is expedient to preface the discussion by considering the content of the concepts and terms we use.

Kachar deposit (North Kazakhstan) is a complex object. It includes independent deposits of magnetite, copper, polymetallic, alunite and other ores, although in the literature is known only as a deposit of magnetite ores.

Since the 70's in the north of the Central Taymir, considerable attention has been paid to quartz and carbonate-quartz veins with polysulfide mineralization, which is due to the isolation in the Taymir quartz (sulfide)-gold ore formation.

Identification and meaningful analysis of indicator features of chemical composition and physical properties of rocks and ores in different structural-formational position and metamorphism of ultramafic complexes is essential for petrology and metallogeny.

The study of geochemistry of zonal phenite halos - determination of the full spectrum of chemical elements taken out of the magmatic body and revealing the nature of their distribution in the zones of the metasomatic column - is an actual task of the study of alkaline metasomatites, the solution of which has a certain prospecting value.

In A.N.Zavaritsky's works the questions of geology of sorcery and contact-metasomatic deposits occupy a great place. Suffice it to mention the works on the establishment of interrelationships of sorcery deposits with volcanism and a fundamental monograph on "Magnitnaya Mountain and its iron ore deposits".

Many ore bodies of tin deposits of South-Eastern Primorye, characterized by insignificant depth of erosion cut, have a distinct vertical zonality, expressed in the replacement with depth of weakly tin-bearing essentially sulfide (polymetallic) mineral associations with low-sulfide cassiterite-bearing.

Mineralized domes - one of the most common morphological types of greisen - are of interest not only from a practical point of view as concentrators of tin, tungsten, molybdenum and other rare metals, but also in terms of studying the vertical zonation.

Among the gold deposits of the North-East of the USSR, attributed to the gold-quartz formation, a special morphological type of mineralization in dyke rocks.

Quartz veins are natural objects with which industrial concentrations of ore mineralization are associated and which themselves can be bodies of minerals - raw materials for smelting various types of quartz glass.

Weathering and erosion processes destroy the native tin deposit, but the placer collects and concentrates its useful component - cassiterite.

All bauxite deposits of Northern Kazakhstan are of Mesozoic age of continental type and are represented by hydrargillitic ores. The largest of them are located within the western side and central part of the Turgai Trough and the southeastern slope of the Kazakhstan Shield (respectively, deposits of the West-Turgai, Central and Amangelda bauxite-ore districts).

The study of composition, structure, conditions of formation and changes in sedimentary formations of the marginal parts of the platforms, taking into account the inseparable connection of their development with tectonic movements in the basin of sedimentation and in the adjacent folded and platform areas, allows to find out the regularities of location of associated deposits and manifestations of minerals.

The question of the meaningful connection and relationship between stratigraphy and cyclostratigraphy arose with new vigor in the 1970s as a result of the successful development of sedimentary cyclicity.

Carbonate rocks of the Silurian of Tuva are of exclusively organogenic origin. In Central Tuva they form a significant part of the Silurian strata, are the most diverse in structure and origin.