The peculiarities of are considered in terms of mica-bearing pegmatites of the Karelian, Kola and Mama and Vitim mica-bearing provinces and chamber pegmatites of Central Kazakhstan. Special attention is paid to the influence of physical and mechanical properties of enclosing rock on the shape and occurrence of pegmatite bodies and their association with post-folded faults.
The new data on geology of Devonian graben and subjacent complexes allow reviewing the evolution of geodynamic processes in this region during Riphean-Paleozoic. It was confirmed that Cambrian – Early Silurian series were formed in the platform environment under conditions of stable dome-like uplifting of the territory, and the subalkaline granitoids (S2-D1) may be classified as anorogenic intrusion. Devonian riftogenesis was a sequel of regeneration of the Riphean paleo- rift in conditions of general spreading. There are distinguished three stages in formation of the graben: pre-graben, orogenic and post-orogenic ones, with description of complexes formed at those stages. Concluding processes of this type are related to formation of fluorite-barite-рolymetallic occurrences and alkaline-ultrabasic dykes (D3) in zones of deep faults. The conclusion is made that the crust block, representing basement of the Barenz-sea plate in the region, has gone through the recurrent intra-plate riftogenesis in the Middle Paleozoic.
A new metallogenic zone was separated out in a central part of the archipelago Spitsbergen by the results of exploration work. It was shown an integral series of ore areas and fields in the limits of this zone, including the ore field Halvdanpiggen. This field integrates several non-uniformly scaled the ore occurrences, which present a great interest in regard to a material composition of the ore. They likewise produce an information for determination of genesis and outlooks of total metallogenic zone. The article contains data on geology, mineralogy and geochemistry of deposits; it is established their genesis, formation membership and time of origination.
Application of decryptometric survey for disassembling bearing rare-metal mineralization of granite massif of East Transbaikalia gave positive results. Two types of decryptograms are observed. The first one, with a distinct maximum in the temperature range of 300-550 °С, is characteristic for samples from steaming halos of unpromising Taptanai and Sakhanai massifs. The second, with distinct maxima at temperatures of 120; 250 and 400-600 °С, is characteristic of samples from the halos of the Dedonogorsky and Etykinsky massifs, which are associated with industrial rare-metal mineralization.
Deposits of rock crystal in the Subpolar Urals were discovered in the thirties, when exploration work with the purpose of finding primary sources was based on the findings of surface placers of quartz crystals. Later, the main attention of geologists who studied and explored rock crystal deposits was directed to the study of conditions of formation and regularities of location of crystal bodies. Great progress has been made in solving this problem, and at present a considerable number of indirect signs have been established that indicate the possibility of finding blind nests of rock crystal in a given area.
One of the essential questions arising in the analysis of ore field structures is to establish the measure and nature of the influence of the specific physical and mechanical properties of the host rocks on the shape and spatial position of ore objects. Interesting materials on this iss. were obtained during the study of deposits of Suraizskoe crustalene field of the circumpolar Urals. A great role belongs here to the type of structures of unlensing developed in the host rocks.