Vol 33 Iss. 2

Professor of the Leningrad Mining Institute, Doctor of Geological and Mineralogical Sciences M.M. Tetyaev was born on September 11 (23), 1882. In 1900. M. M. Tetyaev entered St. Petersburg University at the natural department of the Faculty of Physics and Mathematics, but in February 1901 he was expelled for participation in the student movement and by the verdict of a special meeting was surrendered to the soldiers. Soon he was released and returned to classes, and in 1902 he was again expelled from the university without the right to return.M. M. Tetyaev continued his higher education abroad at the University of Liège, at the School of Mines of the Faculty of Mechanics. There in 1911 he received the title of mining engineer, and in 1912, after defending his thesis at the Faculty of Natural Sciences, the academic title of engineer-geologist.

The Leningrad Mining Institute, the entire geological community of our country and especially coal geologists suffered a great loss - on January 9, 1957, at the 72nd year of his life Yuri Apollonovich Zhemchuzhnikov - the oldest professor of the Institute, corresponding member of the USSR Academy of Sciences - died. The glorious creative life path of the greatest scientist, talented teacher, who gave all his strength and abilities to serve our Motherland, was interrupted. Yuri A. Zhemchuzhnikov was born on April 26, 1885 in Samara. In 1902 he graduated from a real school in St. Petersburg and in 1903 entered the Mining Institute. He was expelled from the institute in 1904 for participation in student strikes. Returning then to the institute in 1908, he graduated in 1915 with an exploration specialty.

The problem of transgressive and regressive phenomena in the accumulation of sediments entered a new phase. This was due to the study of coal-bearing formations with regard to the cyclic nature of their structure. In lithologic works on the Kuznetsk, Karaganda and other basins, and especially on the Donetsk basin, the importance of sedimentary cycles consisting of regressive and transgressive parts became clear. It was further established that regression does not repeat in reverse order the rocks and facies of the transgressive part of the cycle. It is characterized by a number of facies with special features, if even they develop at the same depths and the same distances from the shore as the transgressive facies. The respective rock features also bear the features of differences that are more and more revealed.

The problem of the preconditions of coal formation needs periodic revision because of the continuous progress in the various fields of geological science and the critical testing of many of its positions on the basis of a dialectical outlook and historical comparison. Many things in coal geology that were constant and fixed in the provisions of Western European manuals and seemed immutable and that were derived from the study of Middle Carboniferous coal in practice turned out to be incomplete, one-sided and wrong in the application to coal accumulation of younger coal-bearing epochs.When considering the whole variety of coal basins of different ages, it is striking, first of all, the variability of conditions favorable to coal accumulation from period to period. The idea of some standard optimal conditions and necessary prerequisites of coal formation should be discarded and replaced by the idea of irreversible development of these prerequisites in time and space.

Shallow folds, dome- and ridge-shaped diapiric intrusions into overlying layers, shallow flattening and other manifestations of the so-called secondary tectonics within thick lignite deposits have received repeated coverage in the literature. Secondary tectonics of Ukrainian lignite deposits was studied by V.N. Chirvinsky, I.E. Slenzak, M.N. Karlov, V.T. Seryay; of German lignite deposits - by W. Gotan, K. Jurassky and others; of Korkinskoye deposit - by G.F. Krasheninnikov, O.I. Pinchuk; of Babaevskoye - by A.S. Khomentovsky and V.V. Kiryukov. Kiryukov. Diapiric phenomena complicate the development of coal deposits, exploration by the usual method does not establish the location and scale of diapiric phenomena. Most of the diapirs were discovered only in the process of exploitation of the deposits. The author of this article during 1952-1956 studied and documented on the exposed walls of the coal seams of Babaevsky, Mayachny (Southern Urals) and Alexandriysky (Ukraine) deposits various diapiric intrusions of the coal deposit into the overlying rocks and developed a hypothesis of their origin.

Low-metamorphosed brown coals of Tertiary age, widely distributed within the right-bank Ukraine, southwestern Urals and northern Kazakhstan from the petrographic side are insufficiently investigated. There is still no well-developed methodology for studying low-metamorphosed loose brown coals, which differ sharply from denser brown and hard coals, as well as from peats. In the present article the results of complex (botanical, petrographic and chemical) study of the material composition of low-metamorphosed brown coals composing a thick deposit of the Babaevskoe deposit are presented and their comparison with coals of other Tertiary deposits of the southwestern Urals is given. The questions of the origin of low-metamorphosed brown coals are considered by the author in a special article; a detailed characterization of the types of coals and the structure of coal deposits of individual deposits of the South Ural brown-coal basin is set forth in the atlas currently being prepared.

In engineering geology, clayey rocks are considered as some multiphase systems consisting of mineral particles, water and air. The mineral particles, forming the skeleton of the rock, are in most cases the main constituent of the rock. Water and air fill the spaces between the mineral particles in the rock pores. The rock pores may contain only air or only water, or air and water together. In some cases, the water filling the rock pores may be in a solid state (as ice). The degree of moisture in the clay rocks changes their state and they can be two or three or in some cases even four-phase systems.

Upper Proterozoic strata of metamorphic rocks on the right bank of the Erzin River, west of its right tributary (Ular River), A.V. Ilyin and V.M. Moralev subdivided into two series: lower - terrigenous and upper - carbonate. Two formations are distinguished in each of them: the Teschemian and Mugurian, Balaktykkhemian and Chartisian. A brief description of the section (from bottom to top) is as follows...

In the geological structure of the studied area are rocks of formations. С² and С³ coal-bearing strata of the middle Carboniferous, which come to the surface in the form of a narrow (0.5-2.5 km) strip along the axis of the Main Donetsk anticline, called in this part Gorlovskaya. To the north and south of this band, the rocks of the overlying coal-bearing formations that form the wings of the fold come to the surface. The rocks here have a steep (50-65°) dip, and their outcrops extend almost linearly in the west-northwest and east-southeast directions.The axial part of the anticline is complicated by shallow folded forms and a large number of discontinuities, different in age and character.

Most researchers of rock crystal deposits, the Subpolar Urals believe that the components that make up the nest minerals are carried by hydrothermal solutions from the magmatic hearth. Let us see to what extent this widespread opinion is confirmed by the actual material during a more or less detailed study of the composition of the host rocks and crystal nests.The striking similarity of the bulk chemical composition of the minerals of the crystal nests and the host rocks is striking even at a cursory acquaintance with chemical analyses. Chemical analyses show that the minerals of crystal nests of the circumpolar Urals consist of the following components: SiO2, Al2O3, FeO, MgO, CaO, Na2O, K2O, Fe2O3, TiO2, MnO, H2O и CO2. All these components are also included in the rocks hosting the crystal nests. Characteristically, the quantitative ratios between the above components are almost identical both in the total composition of the nesting minerals and in the rocks hosting the crystal nests.

Graphic granites by the peculiarity of their structure have long attracted the attention of researchers. It is known that these rocks are similar to ordinary granites in their chemical and mineral composition, but all the quartz in them is enclosed within feldspar crystals in the form of numerous correctly oriented inclusions. The latter often resemble the pattern of ancient graphics. This peculiarity of the rock structure determined their name: runites, Hebrew stone, graphic pegmatites, pegmatite and the most accepted in our literature - graphic granites. Graphic granites are part of various geologic formations. They are known in dikes of acidic igneous rocks, in the apical parts of granite massifs, as part of strata of deeply metamorphosed rocks such as gneisses and others. The most spectacular and coarse-grained samples of written granites are found in pegmatite veins. It was here that they were studied in detail, and their first descriptions are more than a century and a half old. Since then a great deal of work has been devoted to the study of graphic granites and especially to a discussion of the genesis of these rocks.

Touching upon the issue of zircon crystals formation in alkaline pegmatites, the author relies mainly on the results of processing the material collected during the study of mariupolites - alkaline rocks developed in the Azov part of Ukraine. However, review of the literature shows that, apparently, the nature of zircon occurring in other alkaline complexes is quite identical. The solution of this problem is closely related to deciphering the peculiarities of the formation of the host zircon mariupolites, therefore, the main features of the genesis of mariupolites are discussed below in the form in which they were reported at the meetings of the Fedorov session.

In 1948 and 1949, the author of the article was a participant in the search and exploration of volcanic deposits of nugget sulfur on the islands of the Great Kuril Ridge - Iturup and Kunashiri. The materials obtained during this work were the basis for the proposed article. Unfortunately, some questions of geology of the studied sulfur deposits are insufficiently covered in the article, since a number of materials are located outside Leningrad. At the same time, we managed to take into account some new ideas of Japanese geologists on the issues raised. Some of them were borrowed from unpublished translations by G. M. Vlasov. The author also used the reports on work in the Kurils by R. Ostroumov. To both one and the other the author expresses his gratitude.

In 1933 we identified within the Kalbinsky Ridge, and in 1934-1935 we studied in more detail the Upper Paleozoic sediments.Later on, the question of the Upper Paleozoic of the Kalba was dealt with by a number of researchers, the common drawback of whose works was poor knowledge of the peculiarities of the Upper Paleozoic sediments over the entire area of their distribution in the Kalba. As a result, there was some confusion in the ideas about the sequence of the Upper Paleozoic formations, the correlation of these formations and their paleontological and lithological characterization.

The Omsk syneclise is composed of Jurassic, Cretaceous and Tertiary sandy-clayey sediments. These are almost undislocated and non-metamorphosed sedimentary rocks with no effusive or intrusive formations. The thickness of sedimentary rocks lies on the eroded surface of the folded basement, which has a two-tiered structure in most of the territory of the syneclise. The upper tier is represented by effusive-sedimentary rocks, weakly dislocated and weakly metamorphosed, within which there are strata with different degrees of dislocation and separated by erosion surfaces. The rocks appear to be of Lower Jurassic to Devonian age. For example, in Barabinsk the structure of the upper tier of the basement is as follows. In the interval of 2215-2234 m lie tuffites, sandstones and mudstones of Lower Jurassic - Upper Triassic age with dip angles of 5-8°. Below, from the depth of 2234 m to the bottom of the well stopped at the depth of 2470 m, the rocks are argillites with thin interbeds of tuffogenic sandstones and tuffs. These layers are inclined at an angle of 45°. Initially, the age of the rocks, determined by spore analysis, was considered to be Upper Devonian, later it was considered to be simply Paleozoic.

The existing petrographic classification understands tuffites as complex rocks with pyroclastic and subordinate quantitatively normal sedimentary material. The content of the latter is most often specified in the range of 10-15%. Such a peculiar composition of tuffites results from the specific conditions of their formation, when the products of volcanic eruptions and sedimentary, most often clastic material are simultaneously accumulated in the water basin, mixing with each other. Naturally, organic remains, important to the geologist and usually of little importance in the construction of the rock, may also be found in the composition of such a rock.

The usual methods of quantitative analysis in general do not allow to establish the phase composition of the mixture. Knowledge of the phase composition of carbonate rocks in a number of cases is of interest in geological surveys, technological processes of processing of these rocks, etc. So, for example, for a mixture of carbonate rocks quantitative analysis gives only the total content of calcium and magnesium, and to establish by this method the number of individual phases (calcite, dolomite and magnesite) in their combined presence is not possible.

The proposed sampling method is based on a regular relationship between the structure of ore deposits in terms of thickness and the content of valuable mineral. The main object of the study was a deposit where the largest ore deposits are genetically and spatially associated with a primary well stratified rock complex. The main reason for the formation of stratified complex of rocks and ore deposits is crystallization differentiation, which apparently consisted in the following: a) movement of crystallizing magmatic melt; b) gravity; c) large accumulation of elements giving volatile compounds; d) increasing viscosity of crystallizing melt; e) non-uniform (consecutive from top to bottom) cooling of the intrusive body; f) two periods of melt crystallization: first - slow crystallization of mainly leucocratic minerals, second - faster crystallization of all other minerals of magmatic origin.

Methods of spectral analysis are widely used in the practice of geological exploration. Of great importance for the needs of geology are those methods that are based on simple and accessible techniques of spectral analysis, provide good performance, the possibility of determining a large number of chemical elements on the spectrum of the sample and give a quantitative characterization of the elements determined. Such a method is currently the method of full spectral analysis, when the sample is introduced into an electric arc and for quantitative assessment is used attenuation of the intensity of spectral lines by three orders of magnitude. The content is determined by plotting the number of analytical line steps against the concentration of the element in the samples. However, the process of evaporation and excitation of a particular element depends on the composition of the sample being analyzed. Therefore, the intensity of lines at the same concentration of the element can be different in samples of different composition.

Gulshad polymetallic ore deposits are located in the thickness of marbleized limestone and crystalline shale of Silurian age. Ore zones of deposits, confined, as a rule, to tectonic disturbances, have a complex geological structure. The main ore deposits are usually lenticular (often irregular) in shape and are accompanied by smaller bodies located in parallel and in a clump-like manner. The presence of interlayers of carbonaceous shale at the contacts of ore bodies with limestone and in ore intervals is the reason for frequent core drilling in these places. Core recovery from ore intervals in many wells is 30-45%, and in some wells it drops to zero. All this complicates exploration drilling works and makes it difficult to calculate reserves. In 1951-1953, the author tested the possibilities of electrical carotage for determining the thickness of ore bodies and refining geologic sections along drilling profiles.

Usually used in direct current electrical prospecting, the approximate method of taking into account the influence of the earth's surface consists in doubling the values of the electric potential found for the case of a body in an electric field in an unrestricted host medium, i.e., in the absence of an earth-air interface.In the present paper we analyze the errors introduced by the above method of taking into account the influence of the flat earth surface for bodies of regular geometric shape. For this purpose, for the approximate potential curves calculated using the usual doubling technique, such a shape of the body surface is selected for which the solution obtained by doubling is absolutely accurate.