No 4 (2024)
Scientific articles
Mineralogical and geochemical analysis of metal jewelry from burial 59 of Kokpomyag burial ground of Vym culture in Vychegda Perm of the 11th—14th centuries
Abstract
The article is devoted to the archaeological and mineralogical analysis of metal products from burial No. 59 from the Kokpomyag burial ground of the Vym culture in Vychegda Permian; dating from the mid-12th to the first half of the 13th century. The chronological framework of the burial is determined; a description of the grave goods is given; and imported silver jewelry from the Perm Kama region and Volga Bulgaria is found. Using analytical SEM; 13 artifacts of copper; bronze; brass and silver composition; the phase and chemical composition of the objects have been studied in detail. The results of the research indicate that Perm foundry workers from Vychegda possessed not only the technology of bronze foundry production; but also silver jewelry making.
3-20
Lithological characteristics of the Kolgan formation of the south-western part of the East Orenburg arch uplift
Abstract
Based on the study of core material; the lithological features of the deposits of the Kolgan formation of the Frasnian stage in the southwestern part of the East Orenburg arch uplift are considered. This formation is an important oil and gas play. Since picking; almost nonintermittent prospecting and exploration works have been carried out. A large bulk of heterogeneous material is received and processed; which complement and expand the knowledge of the geological structure and genesis of sediments. The research was carried out by petrographic and lithological methods. As a result; 5 lithotypes were identified according to the ratio of carbonate and terrigenous components and structural and textural features. It was found that the carbonate component prevailed in all the selected lithotypes; which distinguished this formation from other similar sections; where terrigenous rocks predominated. The presence of bioturbation of varying degrees of intensity and the presence of tempestites is characteristic.
21-26
Concentration flows. 230 years in the crystallogenic agenda
Abstract
We briefly outlined the history of discovery and study of concentration flows accompanying the growth and dissolution of crystals in solutions. Various crystallogenic consequences associated with concentration flows (changes in the mechanisms of transport of matter to the growing crystal; differences in the growth of the upper and lower faces; distortion of crystal shape; occurrence of hydrodynamic boundary layer around a crystal together with the diffusion layer; etc.) were described. The phenomenon of concentration differentiation (stratification) of the solution under the influence of concentration flows was especially analyzed. The criteria conditions for differentiation of the solution during crystal growth were determined.
27-33
From teaching experience. XIV. On the variety of tetrahedrons
Abstract
The paper proposes the derivation of 25 combinatorial-geometric kinds of tetrahedrons belonging to 8 point symmetry groups. Among them are 3 simple forms: cubic (-43m); tetragonal (-42m) and rhombic (222) tetrahedrons; and 5 combinations: trigonal pyramid and monohedron (3m); 2 planar dihedrons (mm2; 2 kinds); 2 axial dihedrons (2; 3 kinds); planar dihedron and 2 monohedrons (m; 5 kinds); 4 monohedrons (1; 11 kinds). It is shown that tetrahedrons with symmetry 23; -4 and 3 — subgroups of the point symmetry group of the cubic tetrahedron — are impossible. The example is recommended for consideration in the course of crystallography on «simple forms and their combinations».
34-37
Chronicle, events, facts. History of Science
The 18th Geological Congress of the Komi Republic
Abstract
On April 10—12; 2024; the 18th Geological Congress of the Komi Republic “Geology and mineral resources of the European North-East of Russia” was held. Geologists from various regions of the Russian Federation and abroad took part in the Congress. Plenary reports and sessions discussed key problems of geology; results of geological exploration over the past period; the development and use of the mineral resource base; and prospects for the development of the most important branches of the mining industry.
38-50