Search

The article discusses the features of the geological structure and composition of the magmatic rocks of the Nizhnetaezhny ore district (North Primorye). It ncludes the East Sikhote-Aligna Volcano-plutonic belt (ESAVPB) and is located in the transition zone Continent Ocean. ESAVPB is the typomorphic link of the East Asian Occinno-Continental Volcanogenic, reconstructed by A. I. Khanchuk as an oversumbays. Other links are known as the Okhotsko-Chukchi, Busan and Southeast Chinese belts. To determine the age of the magmatic arrays, the NTOD selected from the two most representative intrusive bodies of the node of the Malinovsky and Berezovsky massives, between them the main mass of ore mineralization is located. The determination of the ages of the K-Ar method is shown that quartz diorites were formed in Paleocene (64 ± 1 million years), and biotite porphyrene granites in Eocene (47 ± 2 million years). It was previously assumed that the Malinovsky massive is a typical representative of Primorsky, and Berezovsky and the Zavodskoy - Samarka or Bogopolskaya volcanic Plutonic Comlex. Considering that some definitions show (62 ± 1 million years) and characterize porphyry dacites in the Exocontact attacked of the Berezovsky massive, and in the bottom of the incision of the bogopolskaya suites, the lumpy tuffs of rhyolitic and touff-conglomerates contain retalized and half-rolled fragments of the myarol granites common in the Primorsky complex, we can conclude About accessories Malinovsky and Berezovsky massive to the Samarkinskiy complex. In favor of such a conclusion, the determination of the age of monzodiorite (64 ± 1 million years) and pyroxene diorites (57 ± 2 million years) of the Malinovsky massive, which are consistent with the refined rates of the age of the Samargna suite, are appropriate.

Lockated in the noth part of Primorsky region, the Kumirnoe silver deposit is very interesting object from a geological point of view. Data about isotopic mineralogical characteristics of its ore mineralization was first presented in this essay. More than 80 ore bodies are known at the deposit. They mostly contain quartz, hydromica, sericite, adularia, chlorite, montmorillonite and kaolinite. Ore mineralization is represented by silver-bearing minerals: acanthite, pyrirargyrite, polybasite, stephanite, freibergite, selenium-containing aguilarite and eletrum. The obtained isotope data indicate that sulfur composition is close to meteorite standard, this is indicated by the narrow positive interval of its sulfur ratios (2,0-2,8‰). It gives the reason to assume that homogeneous hydrothermal ore-forming solutions participated in its formation. Its comparison with isotopic data of gold-silver deposits located in the continental marginal volcano-plutonic belts (Ducat, Mnogovershinnoe, Sergeevskoye) shows that the formation of the Kumirnoe deposit was at the same time: Cretaceous- Paleogene, it’s possible it was under similar geological conditions. This is confirmed by the age data obtained by us earlier for Kumirnoe deposit (it matches Cretaceous- Paleogene).

This article is about features of geological structure and composition of volcanic and sedimentary rocks of the Low Taiga area (Russia, Primorsky region). This area is a part of the east Sihote-Alin volcanoplutonic belt, is located in the area of transit from the continent to the ocean. Studings of geological and chemical composition, structure and patterns of placement of the Low Taiga Area’s volcanic sedimentary rocks allow us to complete information about geological and geochemical features of Mesozoic-Cenozoic stage of the formation of the said structure. Unever igneous formations are distributed within this area, classified to Primorsky (turonian senonian), Samarga (maastrichtian), Bogopolsky (Paleocene) and Kizinsky (Miocene) volcanic complexes. Matching volcanic rocks complex’s chemical composition with published data testifies to significant similarity with petrotypes of ternei volcano structure. Besides it was found that the Low Taiga Area’s complexes contain high potassium varieties and vary in contents of rare and rare earth elements. Distribution of incoherent elements of primorsky complex’s volcanics are characterized by increased concentrations of tungsten, zinc, plumbum, thorium, lanthanum, cerium, by low content of niobium, strontium, zirconium and titanium. Samarga complex is characterized by low content of titanium and strontium, by low content of neodymium. Bogopolsky and Kizinsky complexes in the distribution of rare and trace elements have a similar trend appearance with petrotypes, but differ in the level of their concentration.

In this work, to study the vertical extent of mineralization, determine the level of erosion, and identify signs of longitudinal placement of silver mineralization of the Nizhnetaezhny ore district (NOD) For this, the main indicator indicators Ag, Au, Cu, Zn, Pb were identified based on the maximum correlation coefficient, Sn, Sb, As, Mo. Then, the ratios of the linear productivities of the indicator elements for the main ore zones of the Scientific and Technological Logging were made: Kumirnoe - Sb * Ag * As / Cu * Sn, Kabaniy - Sb * As * Ag / Cu * Sn, SredniySukhoy - Sn * Pb * Zn / Au * As, Levoberezhnoe -Sn * Pb * Zn / W * Mo. The obtained geochemical data of changes in the multiplicative coefficients allowed us to identify areas according to their erosion: weakly eroded (Kumirny, SredniySukhoy) and significantly eroded (Kabany, Levoberezhnoe), and then divide them into upper ore, ore and under ore. At all sites (except for the SredniySukhoy), at the level of the conditionally subsided horizon, a tendency of gradual increase in productivity was revealed, which indicates the long-range placement of productive ore zones and makes it possible to suggest the presence of powerful and productive silver zones hidden at depth. The data obtained provide the prerequisites for the revaluation of the prospects of the deep horizons of the NOD silver mineralization.

Nizhne-Taezhnyi ore node of Northern Primorye is a complex object containing tin-polymetal-silver, polymetal-silver, and proper silver mineralization silver-porphyry mineralization is possible to be found also. Analysis geogimicl element distribution showed that Ag and Sb with good correlation between each other manifested a weak tendency to decrease with depth. The highest concentrations of Sn, Pb, and Zn are fixed at a depth of about 250 m and decrease upwards and downwards from this level, but Mo and Cu contents essentially increase at low levels (Fig. The revealed tendencies of variability of the chalcophile element concentration both laterally and vertically can be explained by the availability of a vertical mineralogical-geochemical zonality of the mineralization.