The phanerozoic volcanism and mineral resources of the Eurasian Arctic

The Arctic region of Eurasia has a serious lag in the geological study of manifestations of volcanic activity and associating minerals. The results of geological surveys conducted here on a scale of 1:1000000 revealed the basic elements of geology, tectonic structures and major mineragenic taxa of the continental land, arctic islands, the bottom shelf seas and adjacent waters of the Arctic Ocean. For example, in the atlas of paleovolcanic maps with a scale of 1: 5 000 000 published by VSEGEI and edited by I.V. Luchitsky, T.V. Dzhinelidze, A.D. Shcheglov et al. in 2001, the basis of division into districts were two defining factors: scales of distribution and duration of existence of volcanic provinces, belts, areas, zones and regions of the continental part of Northeast Eurasia. The latest data obtained by the author as a result of long-term field research on the archipelagos: Spitsbergen, Novaya Zemlya, Franz Josef Land, in the Arctic Yakutia and on the Chukotka peninsula, supplement the information of the atlas on volcanite geology and miner-ageny of the adjacent Arctic islands and shelf. The volcanic formation is defined according to the accepted concept as a generalized model of association of volcanic rocks with similar features of content, structure and ratio with the environment, steadily repeating in geological space and time. Manifestations and mineral deposits of the following groups are associated with volcanic formations: ferrous metals, non-ferrous metals, precious metals and non-metallic minerals. By the genetic basis ore formations are divided into: a) volcanic-sedimentary stratiform formations associated with specific volcanic formations, they are usually at a distance from the volcanic edifices; b) ore formations of pyrites orebodies of the volcanic zone; c) ore formations, deposits of which are directly related to the volcanic rock or a separate volcanic body; d) volcanogenic-hydrothermal subvolcanic subsurface ore formations paragenetical-ly associated with propylitic metasomatites, characterized by mineralization of the structure of the ore bearing volcanogenic formations; e) hydrothermal and hydrothermal-metasomatic ore formations of moderate depths paragenetically associated with intrusive bodies that transect ore bearing volcanites, mineralization is epigenetic to intrusions and stratified volcanites. During the Baikal - Early Caledonian stage of tectonomagmatic reactivation (from Venda to Early Silurian), the overwhelming part of the volcanic-plutonic formations was concentrated on the current territory of the Urals and Western Siberia, dissected by deep rift valleys. In the territories of the Russian and Siberian platforms volcanism manifested only in the marginal parts in a scale small in size and in the power of coating facies. In the conditions of the prevailing processes of stretching there formed long faults of fault and shear types.

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